<PAGE>   1
                                                               EXHIBIT 10.16


                         LEASE AGREEMENT BY AND BETWEEN
                               TEKELEC, as Tenant
                                       AND
                         WEEKS REALTY, L.P., as Landlord
                        PARAMOUNT CENTER, MORRISVILLE, NC


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                                TABLE OF CONTENTS

1.      PREMISES AND TERM.

2.      BASE RENT, TAXES, INSURANCE, COMMON AREA MAINTENANCE, AND SECURITY
        DEPOSIT.

3.      COMPLIANCE WITH LAWS AND USE.

4.      REPAIR AND MAINTENANCE.

5.      ALTERATIONS.

6.      SIGNS.

7.      INSPECTION.

8.      UTILITIES.

9.      ASSIGNMENT AND SUBLETTING.

10.     FIRE AND CASUALTY DAMAGE.

11.     LIABILITY.

12.     CONDEMNATION.

13.     HOLDING OVER.

14.     QUIET ENJOYMENT.

15.     EVENTS OF DEFAULT.

16.     REMEDIES.

17.     LANDLORD'S LIEN.

18.     MORTGAGES.

19.     MECHANIC'S LIENS.

20.     NOTICES.

21.     BROKER'S CLAUSE.

22.     LANDLORD'S LIABILITY.

23.     RULES AND REGULATIONS.

24.     HAZARDOUS MATERIALS.

25.     [INTENTIONALLY DELETED.]

26.     COVENANT OF TENANT.

27.     MISCELLANEOUS.


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EXHIBIT A- THE LAND

EXHIBIT B- FLOOR PLAN

EXHIBIT C- PLANS AND SPECIFICATIONS

EXHIBIT C-1 - SCHEDULE

EXHIBIT C-2 - DESIGN CRITERIA

EXHIBIT D- RULES AND REGULATIONS

EXHIBIT E- ADJACENT PROPERTY 


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                                LEASE AGREEMENT

        THIS LEASE AGREEMENT (the "Lease"), is made and entered into as of the
6th day of November, 1998, by and between TEKELEC, a California corporation (the
"Tenant"), and WEEKS REALTY, L.P., a Georgia limited partnership authorized to
do business in North Carolina as WEEKS REALTY LIMITED PARTNERSHIP (the
"Landlord").

                              W I T N E S S E T H:

        1. PREMISES AND TERM. In consideration of the obligation of Tenant to
pay rent as herein provided, and in consideration of the other terms, provisions
and covenants hereof, Landlord hereby leases to Tenant and Tenant hereby leases
from Landlord, certain premises comprised of 152,372 rentable square feet in a
building to be constructed in a development known as Paramount Center,
Morrisville, NC (the "Building") situated on certain land (the "Land") in the
County of Wake, State of North Carolina, more particularly described on Exhibit
A, attached hereto and incorporated herein by reference, together with all
rights, privileges, easements, appurtenances and immunities belonging to or in
any way pertaining to the premises (hereinafter referred to as the "Premises").
The obligations of Tenant shall commence hereunder upon the Commencement Date
and the delivery of the Premises by Landlord to Tenant.

        A floor plan of the Premises is attached hereto and made a part hereof
as Exhibit B. Except as expressly set forth herein, the Premises are leased by
Tenant "as is". Any upfit performed by Landlord to prepare the Premises for
occupancy by Tenant shall be conducted in a good and workmanlike manner. The
taking of possession by Tenant shall be deemed conclusively to establish that
the Premises and any improvements thereto are in good and satisfactory condition
as of when possession was taken. Tenant further acknowledges that no
representations as to the repair of the Premises, nor promises to alter, remodel
or improve the Premises have been made by Landlord, unless such representations
or promises are expressly set forth in this Lease. Within five days of the
Commencement Date, Tenant shall, upon demand of Landlord, execute and deliver to
Landlord a letter of acceptance of delivery of the Premises, acknowledging the
Commencement Date and Termination Date, the square footage leased, the square
footage of the Building, and the dates for increase in payment of base rent
hereunder. The Letter shall reflect an adjustment of the Commencement Date and
the Termination Date hereunder to reflect the corrected dates for purposes of
this Lease in the event the Premises are not occupied on the Commencement Date
provided in this Lease.

        Notwithstanding anything to the contrary contained herein, Tenant shall
not be required to take any corrective action with respect to any condition or
design which constitutes a latent defect in the Premises by virtue of Tenant's
acceptance of the Premises. If any latent defect affects Tenant's quiet
enjoyment of the Premises, constitutes a dangerous condition or is required to
be corrected by law, then Landlord will undertake the appropriate corrective
action at Landlord's cost. As between Landlord and Tenant, nothing in this
paragraph shall be construed to impose on Tenant or subject Tenant to any
liability to any third party for injury to property or persons arising out of
latent defects unless such latent defects were created by Tenant or its
employees, agents or contractors in the course of repair work or physical
improvements or alterations to the Premises performed by Tenant or its
employees, agents or contractors. As between Landlord and Tenant, nothing in
this paragraph shall be construed to impose on Landlord or subject Landlord to
any liability to any third party for injury to property or persons arising out
of latent defects unless such latent defects were created by Landlord or its
employees, agents or contractors in the course of construction of the upfit of
the Premises by Landlord, its employees, agents or contractors.

        All upfit of the Premises shall be performed by Landlord in accordance
with plans and specifications for the Premises (the "Plans") which are subject
to the approval of Landlord and Tenant, a copy of which shall be attached hereto
and made a part hereof as Exhibit C. Landlord shall provide Tenant with an
allowance in an amount up to .50 per rentable square foot of the Premises for
use by Tenant in its obtaining drawings for the upfit of the Premises. The
drawings obtained by Tenant are subject to the review and approval of Landlord.
The contractor of Landlord shall use reasonable efforts to solicit three bids
from subcontractors for each of the major trades performing upfit of the
Premises, including, mechanical, electrical, plumbing, and drywall.


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        Landlord shall provide Tenant with an upfit allowance for the Premises
in the amount of $20.00 per rentable square foot of the Premises (the "Upfit
Allowance"). The Upfit Allowance shall be used to upfit the Premises based upon
the provisions of Exhibit C. The base building design shall be in accordance
with the Design Criteria, attached hereto and made a part hereof as Exhibit C-2.
Should the upfit costs for the Premises be less than the Upfit Allowance, Tenant
shall be allowed to upgrade the improvements to the Premises, as reasonably
approved by Landlord, to fully utilize the entire Upfit Allowance, to apply any
or all of the remaining Upfit Allowance to the costs of Tenant for architectural
fees, or Tenant may elect to have Landlord apply the remaining Upfit Allowance
(together with the reduced financing costs and commissions of Landlord)
multiplied by a factor of eleven and one quarter percent (11.25%) to reduce the
base rent due hereunder, proportionately over the entire Lease term, all as
reasonably determined by Landlord. Should the upfit costs for the Premises be
greater than the Upfit Allowance, the excess over the Upfit Allowance up to an
amount equal to $25.00 per rentable square foot of the Premises (together with
the financing costs and commissions of Landlord) shall be amortized and repaid
plus interest at a rate of ten and one-half percent (10.5%) per annum,
proportionately over the entire Lease term as Additional Rent, all as reasonably
determined by Landlord (and any current increases in base rent each year shall
remain at the same percentage increase). Any cost and expense incurred by
Landlord in upfitting the Premises in excess of $25.00 per rentable square foot
of the Premises (the "Excess") shall be borne by Tenant and payable by Tenant to
Landlord within thirty days of demand by Landlord to Tenant. Failure by Tenant
to pay the Excess upon demand as aforesaid is an event of default hereunder, and
in addition, to all other remedies available to Landlord at law, or in equity
for such event of default, Landlord may recover from Tenant the cost it incurs
in preparing the Premises for another tenant which amount shall be reduced by
any amounts that Landlord may recoup from a new tenant.

        Attached hereto as Exhibit C-1 is a schedule for the upfit of the
Premises, including the dates by which Tenant must make certain decisions
regarding the Premises (the "Schedule"). Landlord and Tenant shall use diligent
good faith efforts to ensure construction of the Premises remains on schedule in
accordance with the Schedule, provided, however, that in no event shall the
failure of Landlord to deliver the Premises to Tenant on or prior to the
Commencement Date (as hereinafter defined) constitute a default by Landlord
under this Lease.

        TO HAVE AND TO HOLD the same for a term commencing on the date a
temporary certificate of occupancy is issued for the Premises (the "Commencement
Date"), and ending on the date that is one hundred and twenty months (120)
thereafter, unless sooner terminated pursuant to the provisions hereof (the
"Termination Date"). The Commencement Date and Termination Date shall be
extended due to delays beyond the control of Landlord, including, but not
limited to, acts or omissions of Tenant, force majeure, delays in obtaining
permits, licenses or other approvals, acts of God, delays caused by Tenant,
and/or inclement weather, including site conditions or winter weather that
prohibit or adversely affect construction (the "Excused Delays"). In the event
the Commencement Date has not occurred by November 1, 1999 due to acts or
omissions of Landlord (with such date being extended for any Excused Delays),
Landlord shall credit against the first installment(s) of base rent due
hereunder from Tenant an amount equal to one day's base rent for each day the
Commencement Date is delayed. In the event the Commencement Date has not
occurred by November 1, 1999 due to acts or omissions of Tenant (with such date
being extended for any Excused Delays), Landlord shall receive from Tenant on
the Commencement Date an amount equal to one day's base rent for each day the
Commencement Date is delayed. The aforesaid monetary amounts shall act as a sole
and exclusive remedy to each party hereto for any delay in the Commencement
Date.

        Option to Renew. Provided there is no default or event of default by
Tenant under the Lease, Tenant shall have the option to renew the term of the
Lease for one renewal term of five years (the "Renewal Term") at the then
prevailing market rate, as determined by Landlord provided Tenant shall provide
Landlord written notice of its desire to renew the term of the Lease at least
nine months prior to the Termination Date. Failure of Tenant to provide Landlord
with the aforesaid written notice shall render the rights of Tenant to renew or
extend the term of this Lease null and void. Upon the exercise by Tenant of its
option to renew, all of the terms and conditions of this Lease shall apply with
base rent being the then prevailing market rate, and


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Tenant shall have no further rights to renew or extend the term of this Lease.
The date of the commencement of the Renewal Term shall be the date after the end
of the current Lease term.

        Right to Terminate Prior Leases. Effective the Commencement Date herein
and provided that (i) there is no default or event of default under this Lease,
the Lease by and between Landlord and Tenant for Enterprise Center II dated
February 24, 1995 (the Lease, and all amendments thereto shall be referred to
herein collectively as the "Enterprise II Lease"), or the Lease by and between
Landlord and Tenant for Enterprise Center IV dated July 28, 1998 (the Lease and
all amendments thereto shall be referred to herein collectively as "Enterprise
IV Lease"), and (ii) Tenant shall have entered into occupancy of the Premises
upon delivery of same by Landlord as provided herein, Landlord will (1)
terminate the Enterprise IV Lease and the Enterprise II Lease, and (2) release
Tenant from any and all of its obligations under the Enterprise II and IV Leases
(other than the obligation of Tenant to pay rent and all other obligations
thereunder until the termination of each such Lease at the rates and in the
amounts then in effect under such Leases, and any other obligations that
expressly survive such termination, as provided in such Leases).

        Adjacent Land. During calendar year 1999 for so long as there shall be
no default or event of default under the Lease by Tenant, Landlord shall refrain
from leasing to a third party certain land of Landlord located adjacent to the
Land as more particularly described on Exhibit E, attached hereto and made a
part hereof (the "Adjacent Property"). During calendar year 2000 for so long as
there shall be no default or event of default under the Lease by Tenant and
provided Tenant shall pay the interest charges of Landlord and the ad valorem
taxes of Landlord for the Adjacent Property, Landlord shall refrain from leasing
the Adjacent Property to a third party. During calendar year 2001 for so long as
there shall be no default or event of default under the Lease by Tenant, and
provided Tenant shall continue to pay the interest charges of Landlord and the
ad valorem taxes of Landlord for the Adjacent Property and in addition, Tenant
shall pay Landlord an amount equal to an eleven percent (11%) return on the
investment of Landlord in the Adjacent Property, as reasonably determined by
Landlord, Landlord shall refrain from leasing the Adjacent Property to a third
party. Failure of Tenant to comply strictly with any of the aforesaid conditions
precedent shall render null and void all rights of Tenant hereunder with respect
to the Adjacent Property, and Landlord may lease the Adjacent Property without
any obligation or liability to Tenant. Should Tenant fail to lease the Adjacent
Property on or prior to December 31, 2001, Tenant shall have no further rights
with respect thereto and Landlord may lease the Adjacent Property without any
obligation or liability to Tenant.

2.      BASE RENT, TAXES, INSURANCE, LAWN DRIVEWAY AND PAVED PARKING AREA
        MAINTENANCE, SECURITY DEPOSIT.

                (a) Tenant agrees to make monthly payments of base rent to
        Landlord for the Premises ("base rent"), in advance, without demand,
        deduction or offset, in lawful money of the United States, at an annual
        rate in the following amounts:

            Year 1 $11.95 per rentable square foot of the Premises.

            Year 2 $11.95 per rentable square foot of the Premises.

            Year 3 $12.31 per rentable square foot of the Premises.

            Year 4 $12.68 per rentable square foot of the Premises.

            Year 5 $13.06 per rentable square foot of the Premises.

            Year 6 $13.45 per rentable square foot of the Premises.

            Year 7 $13.85 per rentable square foot of the Premises.

            Year 8 $14.27 per rentable square foot of the Premises.

            Year 9 $14.70 per rentable square foot of the Premises.

            Year 10 $15.14 per rentable square foot of the Premises.

                Rent payments for any fractional calendar month at the end, or
        the beginning of the term of the Lease, shall be prorated.

                The first lease year hereunder shall commence on the
        Commencement Date and shall end on the last day of the twelfth full
        calendar month thereafter. The first lease year shall include the first
        twelve (12) full calendar months of the term and any partial calendar
        month occasioned by the commencement of rent on a date other than the
        first


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        day of a calendar month. Each successive lease year shall commence on
        the anniversary date of the first day of the first full calendar month
        of the first lease year.

        (b) TAXES

                Beginning on the Commencement Date and continuing for the entire
        term hereof, Tenant shall pay to Landlord, as additional rental,
        Tenant's pro rata share of all taxes, assessments and governmental
        charges of any kind or nature whatsoever levied or assessed against the
        Land and the Building by any municipality, county, or other governmental
        agency (the "TAXES"), which shall be based upon the ratio of the
        rentable square footage of the Building occupied by Tenant to the total
        rentable square footage of the Building. Tenant shall pay its pro rata
        share of the Taxes in advance in equal monthly installments in such
        amounts as are reasonably estimated for each year by Landlord at the
        beginning of each calendar year during the term, each such installment
        being made along with payments of base rent hereunder. Tenant's share of
        Taxes for the initial year of the term is estimated by Landlord to be
        $.84 per square foot per year or $10,666.04 per month. Landlord shall
        promptly notify Tenant of the total actual taxes assessed against the
        Land and the Building, attaching a copy of the tax or special assessment
        bill and shall specify (i) Tenant's pro rata share thereof, and (ii) the
        excess, if any, of Tenant's pro rata share over Landlord's estimation of
        Taxes for such tax year. Tenant shall pay the excess amount so specified
        to Landlord within fifteen (15) days following receipt by Tenant of
        Landlord's letter. Failure by Tenant to pay Landlord such amount within
        the period designated shall constitute a non-payment of rent by Tenant
        and a default of Tenant's obligation under the Lease, and Landlord shall
        be entitled to all remedies provided for in this Lease upon default in
        payment of rent. If the first year for which Tenant's pro rata share of
        the Taxes are due or the final year of the term hereof do not coincide
        with the calendar year, Tenant's pro rata share of the Taxes for the
        portion of that year shall be prorated according to the number of months
        during which Tenant was in possession of the Premises. In the event
        Landlord's estimation of Taxes shall exceed the actual amount of Taxes,
        the amount paid by Tenant for such year shall be adjusted between
        Landlord and Tenant and Tenant shall receive a credit against the next
        due installment of rent hereunder in such excess amount unless this
        Lease has expired or been otherwise terminated, in which event Landlord
        shall pay to Tenant such excess amount within fifteen (15) days
        following receipt by Tenant of Landlord's letter.

                (c) INSURANCE

                Beginning on the Commencement Date and continuing for the entire
        term hereof, Tenant shall pay to Landlord, as additional rental,
        Tenant's pro rata share of the insurance premiums (the "Insurance
        Expense") for commercial general liability, fire and extended coverage
        on the Building and the Land, which shall be based upon the ratio of the
        rentable square footage of the Building to the total rentable square
        footage of the Building. Tenant shall pay its pro rata share of the
        Insurance Expense in advance in equal monthly installments in such
        amounts as are reasonably estimated by Landlord at the beginning of each
        calendar year during the term, each such installment being made along
        with payments of base rent hereunder. Tenant's pro rata share of the
        Insurance Expense for the initial year of the term is estimated by
        Landlord to be $.03 per square foot per year or $380.93 per month.
        Landlord shall promptly notify Tenant of the total amount of the actual
        Insurance Expense, and at Tenant's request, attaching a copy of the
        Insurance Expense invoice related thereto and shall specify (i) Tenant's
        pro rata share thereof, and (ii) the excess, if any, of Tenant's pro
        rata share over Landlord's estimation of the Insurance Expense for such
        year. Tenant shall pay the excess amount so specified to Landlord within
        fifteen (15) days following receipt by Tenant of Landlord's letter.
        Failure by Tenant to pay Landlord such amount within the period
        designated shall constitute a non-payment of rent by Tenant and a
        default of Tenant's obligation under the Lease, and Landlord shall be
        entitled to all remedies provided for in this Lease upon default in
        payment of rent. If the first year for which Tenant's pro rata share of
        the Insurance Expense is due or the final year of the term hereof do not
        coincide with the calendar year, Tenant's pro rata share of the
        Insurance Expense for the portion of that year shall be prorated
        according to the number of months during which Tenant was in


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        possession of the Premises. In the event Landlord's estimation of the
        Insurance Expense shall exceed the actual amount of the Insurance
        Expense, the amount paid by Tenant for such year shall be adjusted
        between Landlord and Tenant and Tenant shall receive a credit against
        the next due installment of rent hereunder in such excess amount unless
        this Lease has expired or been otherwise terminated, in which event
        Landlord shall pay to Tenant such excess amount within fifteen (15) days
        following receipt by Tenant of Landlord's letter.

        (d)     LAWN, DRIVEWAY, INTERIOR COMMON AREA, AND PAVED PARKING AREA
                MAINTENANCE

                Beginning on the Commencement Date and continuing for the entire
        term hereof, Tenant shall pay to Landlord, as additional rental,
        Tenant's pro rata share of the cost to Landlord of the lawn, interior
        common area, and driveway and paved parking area maintenance related to
        the Land upon which the Premises are located (the "CAM Expense") which
        shall be based upon the ratio of the rentable square footage of the
        Building occupied by Tenant to the total rentable square footage of the
        Building. The CAM Expense shall include, without limitation, the costs
        of lawn maintenance, driveway and parking area maintenance for the
        Premises and for the streets and roadways providing access to the
        Building and the Land, management and supervisory fees, exterior
        lighting maintenance, snow removal, waste removal, repair and
        maintenance of paved areas, cleaning supplies, miscellaneous building
        supplies, sweeper brushes, supplies for materials used in common by all
        tenants of the complex in which the Premises are located, external paint
        for the Building, exterior and interior common area maintenance,
        elevator repair and maintenance, external plumbing for the Building,
        exterior lighting in common areas, insect and pest extermination,
        security guards for the complex in which the Premises are located, signs
        for the complex in which the Premises are located, fuel for vehicles and
        street sweepers used by Landlord in the complex in which the Premises
        are located and miscellaneous maintenance expenses. Tenant shall pay its
        pro rata share of the CAM Expense in advance in equal monthly
        installments in such amounts as are reasonably estimated for each year
        of the term of this Lease by Landlord at the beginning of each calendar
        year during the term, each such installment being made along with
        payments of base rent hereunder. Tenant's pro rata share of the CAM
        Expense for the initial year of the term is estimated by Landlord to be
        $1.71 per square foot per year or $21,713.01 per month. Failure by
        Tenant to pay Landlord said amount within the period designated shall
        constitute a non-payment of rent by Tenant and a default of Tenant's
        obligation under the Lease, and Landlord shall be entitled to all
        remedies provided for in this Lease upon default in payment of rent. In
        the event Landlord's estimation of the CAM Expense shall exceed the
        actual amount thereof, calculated on an annual basis, the amount paid
        by Tenant for such year shall be adjusted between Landlord and Tenant
        and Tenant shall receive a credit against the next due installment of
        rent hereunder in such excess amount unless this Lease has expired or
        been otherwise terminated, in which event Landlord shall pay to Tenant
        such excess amount within fifteen (15) days following the receipt by
        Tenant of Landlord's letter. Landlord shall notify Tenant on an annual
        basis of the actual CAM Expense of Tenant for the Premises.

        (e)     RECONCILIATION OF EXPENSES.

                Landlord shall promptly notify Tenant of the total actual (i)
        Taxes assessed against the Land and the Building, (ii) Insurance
        Expense, and (iii) CAM Expense, attaching a copy of the tax or special
        assessment bill, the insurance invoice, or the calculation of CAM
        Expense, as applicable, and shall specify (i) Tenant's pro rata share
        thereof, and (ii) the excess, if any, of Tenant's pro rata share over
        Landlord's estimation for each calendar year. Tenant shall pay the
        excess amount so specified to Landlord within fifteen (15) days
        following receipt by Tenant of Landlord's letter. Failure by Tenant to
        pay Landlord such amount within the period designated shall constitute a
        non-payment of rent by Tenant and a default of Tenant's obligation under
        the Lease, and Landlord shall be entitled to all remedies provided for
        in this Lease upon default in payment of rent. If the first year for
        which Tenant's pro rata share of Taxes, Insurance Expense, or CAM
        Expense (hereinafter collectively, the "Expenses") are due or the final


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<PAGE>   9
        year of the term hereof do not coincide with the calendar year, Tenant's
        pro rata share of Expenses for the portion of that year shall be
        prorated according to the number of months during which Tenant was in
        possession of the Premises. In the event Landlord's estimation of
        Expenses shall exceed the actual amount of Expenses, the amount paid by
        Tenant for such year shall be adjusted between Landlord and Tenant and
        Tenant shall receive a credit against the next due installment of rent
        hereunder in such excess amount unless this Lease has expired or been
        otherwise terminated, in which event Landlord shall pay to Tenant such
        excess amount within fifteen (15) days following receipt by Tenant of
        Landlord's letter.

        (f)     [INTENTIONALLY DELETED]

        (g)     PROVISIONS TO SURVIVE LEASE TERMINATION

                All outstanding obligations of Tenant under the provisions of
        this Section 2 shall survive the termination of the Lease, for whatever
        reason, or any extension or renewal hereof.

        3.      COMPLIANCE WITH LAWS AND USE.

                (a) The Premises shall be used only for the following purposes:
        for a service center, research and development, and light manufacturing,
        the operation of a cafeteria for use by its employees and visitors, and
        general office use related thereto. Tenant shall conduct no activity
        that will result in the discharge of harmful gases, affluents or other
        wastes or toxic substances. Outside storage, including, without
        limitation, trucks and other vehicles, is prohibited without Landlord's
        prior written consent, not to be unreasonably withheld. Tenant shall at
        its sole cost and expense obtain any and all business licenses and
        permits necessary for its use of the Premises. Tenant shall comply with
        all governmental laws, ordinances and regulations relating to the use of
        the Premises, and shall promptly comply with all governmental orders and
        directives for the correction, prevention and abatement of nuisances in
        or upon, or connected with, the Premises, all at Tenant's sole expense,
        only if caused by Tenant, its agents, employees, licensees, or invitees.
        Tenant shall not permit any objectionable or unpleasant odors, smoke,
        dust, gas, noise or vibrations to permeate in or emanate from the
        Premises, nor take any other action which would constitute a nuisance or
        would disturb or endanger any other tenants of the Building or
        unreasonably interfere with their respective premises. Without
        Landlord's prior written consent, Tenant shall not receive, store or
        otherwise handle any product, material or merchandise which is
        explosive, inflammable, combustible, corrosive, caustic or poisonous,
        other than in the normal course of its business, in which event, all
        such materials shall be handled in accordance with all applicable laws.
        Tenant will not permit the Premises to be used for any purpose or in any
        manner (including, without limitation, any method of storage) which
        would render the insurance thereon void or the insurance risk more
        hazardous or cause the State Board of Insurance or other insurance
        authority to disallow any sprinkler credits. Tenant shall give notice to
        Landlord immediately upon the occurrence of any accident in the Premises
        or upon Tenant's discovery of any defects thereon or in any fixtures or
        equipment located therein or upon the occurrence of any emergency in the
        Premises or the Building.

                (b) Tenant, at its expense, in its use of the Premises and in
        making any alterations, renovations, upfit or modifications of the
        Premises shall comply with all laws, ordinances, orders, rules and
        regulations of state, federal, municipal or other agencies or bodies
        having jurisdiction relating to the use, condition and occupancy of the
        Premises, including, but not limited to, the provisions of the Americans
        with Disabilities Act of 1990, as amended, and with recorded covenants,
        conditions and restrictions applicable for the Land and Building.

        4.      REPAIRS AND MAINTENANCE.

                (a) Landlord shall at its expense maintain only the roof,
        downspouts, gutters, foundation, utility lines located outside the
        Premises and the structural soundness of the


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<PAGE>   10
        exterior walls of the Building in good condition and repair in
        accordance with the standards for buildings of similar size and utility
        in Wake County, NC subject to reasonable wear and tear. Landlord shall
        wash the exterior windows of the Premises on a quarterly basis. Tenant
        shall repair, and pay for, any damage to the foregoing caused by the
        negligence of Tenant or Tenant's employees, agents or invitees, or
        caused by Tenant's default hereunder. The term "walls" as used herein
        shall not include windows, glass or plate glass, doors, special store
        fronts or office entries. Tenant shall immediately give Landlord written
        notice of defect or need for repairs, after which Landlord shall have
        reasonable opportunity to repair same or cure such defect. Landlord's
        liability with respect to any defects, repairs or maintenance for which
        Landlord is responsible under any of the provisions of this Lease shall
        be limited to the cost of such repairs or maintenance or the curing of
        such defect and any costs to repair any resultant damage to the trade
        fixtures of Tenant.

                (b) Tenant shall at its own cost and expense keep and maintain
        all parts of the Premises (except those for which Landlord is expressly
        responsible under the terms of this Lease) in good condition, promptly
        making all necessary repairs and replacements, including, but not
        limited to, windows, glass and plate glass, doors, any special office
        entry, interior walls, finish work, floors and floor covering, heating
        and air conditioning systems, dock boards, truck doors, dock bumpers,
        plumbing work and fixtures and regular removal of trash and debris.
        Tenant shall not be obligated to repair any casualty covered by the
        insurance to be maintained by Landlord pursuant to subparagraph 10(A)
        below. To the extent deemed necessary by Landlord, Landlord shall make
        available to Tenant for its use in effecting repairs, any warranties
        with respect to components of the Building.

                (c) Tenant shall enter into a maintenance contract providing for
        the periodic maintenance of all hot water, heating and air conditioning
        systems and units in the Premises, and removal and replacement of
        filters, and shall enter into a janitorial contract providing for the
        daily cleaning of the Premises. These contracts shall be with parties
        and upon such terms and conditions as shall be reasonably approved by
        Landlord. Tenant shall provide Landlord a copy of such contracts within
        thirty days of the Commencement Date.

                (d) Tenant shall not damage any demising wall of the Building,
        or disturb the integrity and support provided by any demising wall and
        shall, at its sole cost and expense, promptly repair any damage or
        injury to any demising wall caused by Tenant or its employees, agents or
        invitees.

                (e) Tenant and its employees, customers and licensees shall have
        the non-exclusive right to use the parking areas as may be designated by
        Landlord in writing, subject to reasonable rules and regulations as
        Landlord may from time to time prescribe and subject to rights of
        ingress and egress of other tenants. Parking shall be available at the
        Building for the non-exclusive use of Tenant at a ratio of five spaces
        per 1,000 rentable square feet. Included within this ratio shall be
        seven parking spaces located adjacent to the Building near the entrance
        to the Premises that shall be marked as spaces for visitors. Landlord
        shall not be responsible for enforcing Tenant's parking rights against
        any third parties. Landlord may require, at its option, in its sole
        discretion, that Tenant, its employees, invitees, and visitors use
        certain numbered spaces to be designated by Landlord.

        5.      ALTERATIONS. Tenant shall not make any alterations, additions or
        improvements to the Premises (including, but not limited to, roof and
        wall penetrations) without the prior written consent of Landlord, Tenant
        may, without the consent of Landlord, but at its own cost and expense
        and in a good workmanlike manner, erect such shelves, bins, machinery
        and trade fixtures as it may deem advisable, without altering the basic
        character or structure of the Premises or improvements and without
        overloading or damaging the Premises or improvements, and in each case
        complying with all applicable governmental laws, ordinances, regulations
        and other requirements. Tenant shall not make any alterations, additions
        or improvements to the Premises which will contravene


                                       7


<PAGE>   11
        Landlord's policies insuring against loss or damage by fire or other
        hazards, including but not limited to commercial general public
        liability, or which will prevent Landlord from securing such policies in
        companies acceptable to Landlord. If any such alterations, additions or
        improvements cause the rate of fire or other insurance on the Premises
        by companies acceptable to Landlord to be increased beyond the minimum
        rate from time to time applicable to the Premises for permitted uses
        thereof, Tenant shall pay as additional rent the amount of any such
        increase promptly upon demand by Landlord. Any and all alterations,
        additions, improvements, partitions and fixtures erected by Tenant shall
        be the property of Landlord and shall remain at the Premises upon
        termination of the Lease or upon earlier vacating of the Premises. All
        shelves, bins, machinery and trade fixtures installed by Tenant may be
        removed by Tenant prior to the termination of this Lease provided such
        removal may be accomplished without damage to the Premises or to the
        primary structure or structural qualities of the buildings and other
        improvements situated on the Premises. Tenant shall repair any damage to
        the Premises, or the Building as a result of any alteration, or repair
        by Tenant, its employees, agents, invitees, or contractors to the
        Premises.

        6.      SIGNS.

                (a) Tenant shall have the right to install signs upon the
        Premises only when first approved in writing by Landlord, such approval
        not to be unreasonably withheld, and subject to any applicable
        governmental laws, ordinances, regulations and other requirements.
        Tenant shall remove all such signs upon the termination of this Lease.
        Such installations and removals shall be made in such manner as to avoid
        injury or defacement of the Premises, and Tenant shall repair any injury
        or defacement, including, without limitation, discoloration of the
        Building caused by such installation and/or removal.

                (b) Included within the Upfit Allowance shall be signage for the
        Premises that shall include (i) a monument sign on the Land with the
        name of Tenant; and (ii) a sign on the exterior of the Premises. All
        signage shall be in form, substance, color, and shape, subject to the
        reasonable approval of Landlord.

        7.      INSPECTION. Landlord and Landlord's agents and representatives
        shall have the right to enter and inspect the Premises at any reasonable
        time during business hours upon reasonable notice except in the event of
        an emergency when Landlord or Landlord's agents may access the Premises
        at any time and without notice for the purpose of ascertaining the
        condition of the Premises or in order to make such repairs as may be
        required or permitted to be made by Landlord under the terms of this
        Lease or in order to show the Premises to any prospective purchaser or
        lender. During the period that is six (6) months prior to the end of the
        term hereof, Landlord and Landlord's agents and representatives shall
        have the right to enter the Premises at any reasonable time during
        business hours upon reasonable notice for the purpose of showing the
        Premises to any prospective tenant and shall have the right to erect on
        the Premises a suitable sign indicating the Premises are available.
        Tenant shall schedule with Landlord at least sixty (60) days prior to
        vacating the Premises a time mutually agreeable to the parties hereto
        for a joint inspection of the Premises prior to vacating. In the event
        of Tenant's failure to give notice or arrange such joint inspection,
        Landlord's inspection at or after Tenant's vacating the Premises shall
        be conclusively deemed correct for purposes of determining Tenant's
        responsibilities for repairs and restoration.

        8.      UTILITIES. Landlord agrees to provide at its cost, all utility
        line connections into the Premises. Tenant shall pay all charges for all
        water, electrical, telephone, sewer, and other utilities or services
        used on or from the Premises, together with any taxes, penalties,
        surcharges or the like pertaining thereto, including, but not limited
        to, any costs for utilities used by Tenant at the Premises after normal
        business hours, 8:00 AM to 5:00 PM, Monday - Friday. Tenant shall also
        pay for any utility maintenance charges and shall furnish all
        replacement electric light bulbs and replacement tubes required for the
        Premises. If any such services are not separately metered to Tenant,
        Tenant shall pay a reasonable proportion as determined by Landlord of
        all charges jointly metered with other


                                       8


<PAGE>   12
        tenants of the Building. Landlord shall in no event be liable for any
        interruption or failure of utility services on the Premises, unless
        caused by the negligence of Landlord in which event Landlord shall use
        reasonable efforts to effect the reconnection of such services.

        9.      ASSIGNMENT AND SUBLETTING. Tenant shall not sublet the Premises
        in whole or in part or sell, assign, lien, encumber, or in any manner
        transfer this Lease or assign or delegate the management or permit the
        use or occupancy of the Premises or any part thereof by anyone other
        than Tenant without the prior written consent of Landlord, which consent
        shall not be unreasonably withheld. Landlord and Tenant acknowledge and
        agree that the foregoing provisions have been freely negotiated by the
        parties hereto and that Landlord would not have entered into this Lease
        without Tenant's consent to the terms of this Paragraph 9.

                No assignment, transfer, mortgage, sublease or other
        encumbrance, whether or not approved, and no indulgence granted by
        Landlord to any assignee or subtenant, shall in any way impair the
        continuing primary liability (which after an assignment shall be joint
        and several with the assignee) of Tenant hereunder, and no approval in a
        particular instance shall be deemed to be a waiver of the obligation to
        obtain Landlord's approval in any other case. If for any approved
        assignment or sublease Tenant receives rent or other consideration,
        either initially or over the term of the assignment or sublease, in
        excess of the base rent hereunder, or in case of a sublease of part of
        the Premises, in excess of the portion of such rent fairly allocable to
        such part, after appropriate adjustments to assure that all other
        payments called for hereunder are appropriately taken into account,
        Tenant shall pay to Landlord as additional rent one-half of the excess
        of each such payment of rent or other consideration received by Tenant
        promptly after its receipt.

                Anything contained in the foregoing provisions of this section
        to the contrary notwithstanding, neither Tenant nor any other person
        having an interest in the possession, use occupancy or utilization of
        the Premises shall enter into any lease, sublease, license, concession
        or other agreement for use, occupancy or utilization of space in the
        Premises which provides for rental or other payment for such use,
        occupancy or utilization base, in whole or in part, on the net income or
        profits derived by any person from the Premises leased, used, occupied,
        or utilized (other than an amount based on a fixed percentage or
        percentages of receipts or sales), and any such purported lease,
        sublease, license, concession or other agreement shall be absolutely
        void and ineffective as a conveyance of any right or interest in the
        possession, use, occupancy or utilization of any part of the Premises.

        10.     FIRE AND CASUALTY DAMAGE.

        A.      Landlord agrees to maintain standard fire and extended coverage
        insurance covering the Building in an amount not less than 80% (or such
        greater percentage as may be necessary to comply with the provisions of
        any co-insurance clauses of the policy) of the "replacement cost"
        thereof as such term is defined in the Replacement Cost Endorsement to
        be attached thereto, insuring against special causes of loss, including,
        the perils of fire, and lightning, such coverages and endorsements to be
        as defined, provided and limited in the standard bureau forms prescribed
        by the insurance regulatory authority for the State of North Carolina.
        Subject to the provisions of subparagraphs 10(C), 10(D) and 10(E) below,
        such insurance shall be for the sole benefit of Landlord and under its
        sole control.

        B.      If the Premises should be damaged or destroyed by any peril
        covered by the insurance to be provided by Landlord under subparagraph
        10(A) above, Tenant shall give immediate written notice thereof to
        Landlord.

        C.      If the Premises should be totally destroyed by any peril covered
        by the insurance to be provided by Landlord under subparagraph 10(A)
        above, or if they should be so damaged thereby that rebuilding or
        repairs cannot in Landlord's reasonable estimation be completed within
        one hundred and eighty (180) days after the date upon which Landlord is
        notified by Tenant of such damage, this Lease shall terminate and the
        rent shall be


                                       9


<PAGE>   13
         abated during the unexpired portion of this Lease, effective upon the
         date of the occurrence of such damage.

        D.      If the Premises should be damaged by any peril covered by the
        insurance to be provided by Landlord under subparagraph 10(A) above, but
        only to such extent that rebuilding or repairs can, in Landlord's
        reasonable estimation, be completed within one hundred and eighty (180)
        days after the date upon which Landlord is notified by Tenant of such
        damage, this Lease shall not terminate, and Landlord shall, at its sole
        cost and expense, thereupon proceed with reasonable diligence to rebuild
        and repair the Premises to substantially the condition in which they
        existed prior to such damage, except that Landlord shall not be required
        to rebuild, repair or replace any part of the partitions, fixtures,
        additions and other improvements which may have been placed in, on or
        about the Premises by Tenant. If the Premises are untenantable in whole
        or in part following such damage, the rent payable hereunder during the
        period in which they are untenantable shall be reduced to such extent as
        may be fair and reasonable under all of the circumstances.

        E.      Notwithstanding anything herein to the contrary, in the event
        the holder (the "Holder") of any indebtedness secured by a mortgage or
        deed of trust covering the Premises requires that the insurance proceeds
        be applied to such indebtedness, then Landlord shall have the right to
        terminate this Lease by delivering written notice of termination to
        Tenant within fifteen (15) days after such requirement is made by any
        such holder, whereupon all rights and obligations hereunder thereafter
        accruing shall cease and terminate; provided, however, upon its receipt
        of notice from the Holder that insurance proceeds shall be applied
        toward the indebtedness, Landlord shall act reasonably to seek to obtain
        sufficient financing to repair and restore the Premises at an interest
        rate, under terms and conditions, and with a lender all as approved by
        Landlord, in its sole discretion.

        F.      Each of Landlord and Tenant hereby releases the other from any
        loss or damage to property caused by fire or any other perils insured
        through or under either by way of subrogation or otherwise for any loss
        or damage to property caused by fire or any other perils insured in
        policies of insurance covering such property, even if such loss or
        damage shall have been caused by the fault or negligence of the other
        party, or anyone for whom such party may be responsible; provided,
        however, that this release shall be applicable and in force and effect
        only with respect to the loss or damage occurring during such times as
        the releasor's policies shall contain a clause of endorsement to the
        effect that any such release shall not adversely affect or impair said
        policies or prejudice the right of the releasor to recover thereunder
        and then only to the extent of the insurance proceeds payable under such
        policies. Each of Landlord and Tenant agrees that it will request its
        insurance carriers to include in its policies such a clause or
        endorsement. If extra cost shall be charged therefor, each party shall
        advise the other thereof and of the amount of the extra cost, and the
        other party, at its election, may pay the same, but shall not be
        obligated to do so.

        11. LIABILITY. Landlord shall not be liable to Tenant or Tenant's
employees, agents, patrons or visitors, or to any other person whomsoever, for
any injury to person or damage to property on or about the Premises to the
extent resulting from and/or caused by the negligence or misconduct of Tenant,
its agents, employees, patrons or visitors, or of any other person entering upon
the Premises. Tenant hereby covenants and agrees that it will at all times
indemnify, defend and hold safe and harmless Landlord (including, without
limitation, its trustees and beneficiaries if Landlord is a trust), and
Landlord's agents, employees, patrons and visitors from any loss, liability,
claims, suits, costs, expenses, including without limitation attorney's fees and
damages, arising out of any such damage or injury, excluding only injury to
persons or damage to property to the extent such injury or damage is caused by
the negligence, willful misconduct, acts or omissions of Landlord or its agents
or employees, or the failure of Landlord to repair any part of the Premises
which Landlord is obligated to repair and maintain hereunder within a reasonable
time after the receipt of written notice from Tenant of needed repairs.


                                       10


<PAGE>   14
        Tenant shall not be liable to Landlord or Landlord's employees, agents,
patrons, or visitors, or to any other person whomsoever, for any injury to
person or damage to property on or about the Premises, to the extent resulting
from and/or caused by the negligence or misconduct of Landlord, its agents,
employees, patrons or visitors. Landlord hereby covenants and agrees that it
will at all times indemnify, defend and hold safe and harmless Tenant
(including, without limitation, its trustees and beneficiaries if Tenant is a
trust), and Tenant's agents, employees, patrons, and visitors from any loss,
liability, claims, suits, costs, expenses, including, without limitation
attorneys' fees and damages, arising out of any such damage or injury, excluding
only injury to persons or damage to property to the extent such injury or damage
is caused by the negligence, willful misconduct, acts or omissions of Tenant or
its agents or employees, or the failure of Tenant to repair any part of the
Premises which Tenant is obligated to repair and maintain hereunder within a
reasonable time after the receipt of written notice from Landlord of needed
repairs.

        Tenant shall procure and maintain throughout the term of this Lease a
policy or policies of insurance, at its sole cost and expense, insuring both
Landlord and Tenant against all claims, demands or actions arising out of or in
connection with: (i) the Premises; (ii) the condition of the Premises; (iii)
Tenant's operations in and maintenance and use of the Premises; and (iv)
Tenant's liability assumed under this Lease, in which the limits of commercial
general liability shall not be less than $5,000,000.00 with respect to each
occurrence, not less than $5,000,000 with respect to personal injury or death of
a single person, not less than $5,000,000 general aggregate, and not less than
$5,000,000 with respect to products completed operations aggregate.

        All such policies shall be procured by Tenant from responsible insurance
companies with at least an A rating from Best's. Certified copies of such
policies, together with receipt evidencing payments of premiums thereof, shall
be delivered to Landlord prior to the Commencement Date. Not less than fifteen
(15) days prior to the expiration date of any such policies, certified copies of
the renewals thereof (bearing notations evidencing the payment of renewal
premiums) shall be delivered to Landlord. Such policies shall further provide
that not less than thirty (30) days prior written notice shall be given to
Landlord before such policy may be canceled or changed to reduce insurance
provided thereby.

        12. CONDEMNATION.

        A.      If the whole or any substantial part of the Premises should be
        taken for any public or quasi-public use under governmental law,
        ordinance, or regulation, or by right of eminent domain, or by private
        purchase in lieu thereof, and the taking would prevent or materially
        interfere with the use of the Premises by Tenant for the purposes
        provided herein, this Lease shall terminate and the rent shall be abated
        during the unexpired portion of this Lease, effective when the physical
        taking of the Premises shall occur.

        B.      If part of the Premises shall be taken for any public or
        quasi-public use under any governmental law, ordinance or regulation, or
        by right of eminent domain, or by private purchase in lieu thereof, and
        this Lease is not terminated as provided in the subparagraph above, this
        Lease shall not terminate but the rent payable hereunder during the
        unexpired portion of this Lease shall be reduced to such extent as may
        be fair and reasonable under all of the circumstances.

        C.      In the event of any such taking or private purchase in lieu
        thereof, Landlord shall be entitled to receive and retain all awards as
        may be awarded in any condemnation proceedings other than those
        specifically awarded Tenant for a taking of Tenant's personal property,
        loss of business and moving expenses.

        13. HOLDING OVER. Tenant will, at the termination of this Lease by lapse
of time or otherwise, yield up immediate possession to Landlord. If Landlord
agrees in writing that Tenant may hold over after the expiration or termination
of this Lease, unless the parties hereto otherwise agree in writing on the terms
of such holding over, the hold over tenancy shall be subject to termination by
Landlord at any time upon not less than ten (10) days advance written notice, or
by Tenant at any time upon not less than thirty (30) days advance written
notice, and all of the other terms and provisions of this Lease shall be
applicable during that period, except that Tenant shall pay Landlord from time
to time upon demand, as rental for the period of any


                                       11


<PAGE>   15
hold over, an amount equal to one and one-half (1-1/2) the rent in effect on the
termination date, computed on a daily basis for each day of the hold over
period. No holding over by Tenant, whether with or without consent of Landlord,
shall operate to extend this Lease except as otherwise expressly provided. The
preceding provisions of this Paragraph 13 shall not be construed as Landlord's
consent for Tenant to hold over.

        14. QUIET ENJOYMENT. Landlord covenants that it now has, or will acquire
before Tenant takes possession of the Premises, good title to the Premises, free
and clear of all liens and encumbrances, excepting only the lien for current
taxes not yet due, deed of trust(s), or mortgage(s) of record, zoning ordinances
and other building and fire ordinances and governmental regulations relating to
the use of such property, and easements, restrictions and other conditions of
record. Landlord represents and warrants that it has full right and authority to
enter into this Lease and that Tenant, upon paying the rental herein set forth
and performing its other covenants and agreements herein set forth, shall
peaceably and quietly have, hold and enjoy the Premises for the term hereof
without hindrance or molestation from Landlord, subject to the terms and
provisions of this Lease.

        15. EVENTS OF DEFAULT. The following events shall be deemed to be events
of default by Tenant under this Lease:

(a)     Tenant shall fail to pay (i) any installment of the rent herein reserved
within five days after the due date thereof, or (ii) payment with respect to
taxes hereunder, or any other payment or reimbursement to Landlord required
herein, within ten (10) days after the due date thereof.

(b)     Tenant shall become insolvent, or shall make a transfer in fraud of
creditors, or shall make an assignment for the benefit of creditors.

(c)     Tenant shall file a petition under any section or chapter of the
Bankruptcy Reform Act, as amended or under any similar law or statute of the
United States or any state thereof; or Tenant shall be adjudged bankrupt or
insolvent in proceedings filed against Tenant thereunder.

(d)     A receiver or trustee shall be appointed for all or substantially all of
the assets of Tenant.

(e)     Tenant shall desert or vacate all or a portion of the Premises.

(f)     Tenant shall fail to comply with any term, provision or covenant of this
Lease (other than the subparagraphs (a), (b), (c), (d), and (e) of this
Paragraph 15), and shall not cure such failure within thirty (30) days after
written notice thereof to Tenant; provided, however, in the event Tenant is
proceeding with due diligence to effect a cure under this subparagraph (f) and
addition time is needed by Tenant to complete its cure, Landlord shall act
reasonably to grant such additional time.

        16. REMEDIES. Upon the occurrence of any event of default in Paragraph
15 hereof, after the expiration of any applicable grace or cure periods,
Landlord shall have the option to pursue any remedy at law or in equity,
including, but not limited to, one or more of the following remedies without any
notice or demand whatsoever:

        (a)     Terminate this Lease, in which event Tenant shall immediately
        surrender the Premises to Landlord, and if Tenant fails to do so,
        Landlord may, without prejudice to any other remedy which it may have
        for possession or arrearage in rent, enter upon and take possession of
        the Premises and expel and remove Tenant and any other person who may be
        occupying the Premises or any part thereof, with or without judicial
        approval, by any legal means necessary, secure the Premises against
        unauthorized entry; and Tenant agrees to pay to Landlord on demand the
        amount of all loss and damage which Landlord may suffer by reason of
        such termination, whether through inability to relet the Premises on
        satisfactory terms or otherwise.

        (b)     Enter upon and take possession of the Premises and expel or
        remove Tenant and any other person who may be occupying such Premises or
        any part thereof, with or without judicial approval, by any legal means
        necessary, receive the rent thereof; secure the Premises against
        unauthorized entry; store any property located on the Premises at the


                                       12


<PAGE>   16
        expense of the owner thereof and Tenant agrees to pay to Landlord on
        demand any deficiency that may arise by reason of such reletting. In the
        event Landlord is successful in reletting the Premises at a rental in
        excess of that agreed to be paid by Tenant pursuant to the terms of this
        Lease, Landlord and Tenant each mutually agree that Tenant shall not be
        entitled, under any circumstances, to such excess rental, and Tenant
        does hereby specifically waive any claim to such excess rental.

        (c)     Enter upon the Premises, with or without judicial approval, by
        any legal means necessary, secure the Premises against unauthorized
        entry and do whatever Tenant is obligated to do under the terms of this
        Lease; and Tenant agrees to reimburse Landlord on demand for any
        expenses which Landlord may incur in thus effecting compliance with
        Tenant's obligations under this Lease.

        (d)     Accelerate and demand the payment of all base rent and other
        charges due and payable hereunder over the term of this Lease.

        In the event Tenant fails to pay any installment of base rent or
additional rent hereunder within fifteen days of the due date of such
installment, Tenant shall pay to Landlord on demand a late charge in an amount
equal to one percent (1%) of such installment per month to help defray the
additional cost to Landlord for processing such late payment. The provision for
such late charge shall be in addition to all of Landlord's other rights and
remedies hereunder or at law and shall not be construed as liquidated damages or
as limiting Landlord's remedies in any manner. If, on account of any breach or
default by Tenant in Tenant's obligations under the terms and conditions of this
Lease, it shall become necessary or appropriate for Landlord to employ or
consult with an attorney concerning or to enforce or defend any of Landlord's
rights or remedies hereunder, Tenant agrees to pay any and all reasonable
attorneys' fees so incurred.

        Pursuit of any of the foregoing remedies shall not preclude pursuit of
any of the other remedies herein provided or any other remedies provided by law
or equity, nor shall pursuit of any remedy herein provided constitute a
forfeiture or waiver of any rent due to Landlord hereunder or of any damages
accruing to Landlord by reason of the violation of any of the terms, provisions
and covenants herein contained. No act or thing done by Landlord or its agents
during the term hereby granted shall be deemed a termination of this Lease or an
acceptance of the surrender of the Premises, and no agreement to terminate this
Lease or accept a surrender of the Premises shall be valid unless in writing
signed by Landlord. No waiver by Landlord of any violation or breach of any of
the terms, provisions and covenants herein contained shall be deemed or
construed to constitute a waiver of any other violation or breach of any of the
terms, provisions and covenants herein contained. Landlord's acceptance of the
payment of rental or other payments hereunder after the occurrence of an event
of default shall not be construed as a waiver of such default, unless Landlord
so notifies Tenant in writing, and no receipt of money by Landlord from Tenant
after the termination of this Lease or after service of any notice or after the
commencement of any suit or after final judgment for possession of the Premises
shall reinstate, continue or extend the term of this Lease or affect any such
termination, notice, suit or judgment, unless Landlord so notifies Tenant in
writing. Forbearance by Landlord to enforce one or more of the remedies herein
provided upon an event of default shall not be deemed or construed to constitute
waiver of such default or of Landlord's right to enforce any such remedies with
respect to such default or any subsequent default.

        17.     LANDLORD'S LIEN. [INTENTIONALLY DELETED.]

        18.     MORTGAGES. Tenant accepts this Lease subject and subordinate to
any mortgage(s) and/or deed(s) of trust now or at any time hereafter
constituting a lien or charge upon the Premises or the improvements situated
thereon; provided, however, that if the mortgagee, trustee, or holder of any
such mortgage or deed of trust elects to have Tenant's interest in this Lease
superior to any such instrument, then by notice to Tenant from such mortgagee,
trustee or holder, this Lease shall be deemed superior to such lien, whether
this Lease was executed before or after said mortgage or deed of trust. Tenant
shall at any time hereafter on demand execute any instruments, releases or other
documents which may be required by any mortgagee or trustee for the purpose of
further subjecting and subordinating this Lease to the lien of any such mortgage
or deed to trust.


                                       13


<PAGE>   17
        19.     MECHANIC'S LIENS. Tenant shall have no authority, express or
implied, to create or place any lien or encumbrance of any kind or nature
whatsoever upon, or in any manner to bind, the interest of Landlord in the
Premises or to charge the rentals payable hereunder for any claim in favor of
any person dealing with Tenant, including those who may furnish materials or
perform labor for any construction or repairs, and each such claim shall affect
and each such lien shall attach to, if at all, only the leasehold interest
granted to Tenant by this instrument. Tenant covenants and agrees that it will
pay or cause to be paid all sums legally due and payable by it on account of any
labor performed or materials furnished in connection with any work performed on
the Premises on which any lien is or can be validly and legally asserted against
its leasehold interest in the Premises or the improvements thereon and that it
will save and hold Landlord harmless from any and all loss, cost or expense
based on or arising out of asserted claims or liens against the leasehold estate
or against the right, title and interest of Landlord in the Premises or under
the terms of this Lease.

        20.     NOTICES. Each provision of this instrument or of any applicable
governmental laws, ordinances, regulations, or other requirements with reference
to the sending, mailing, or delivery of any notice by Landlord to Tenant or with
reference to the sending, mailing, or delivery of any notice or the making of
any payment by Tenant to Landlord shall be deemed to be complied with when and
if the following steps are taken:

        (a) All rent and other payments required to be made by Tenant to
        Landlord hereunder shall be payable to Landlord at the address
        hereinbelow set forth or at such other address as Landlord may specify
        from time to time by written notice delivered in accordance herewith.
        Tenant's obligations to pay rent and any other amounts to Landlord under
        the terms and of this Lease shall not be deemed satisfied until such
        rent and other amounts have been actually received by Landlord.

        (b) Any notice or document required or permitted to be delivered
        hereunder shall be deemed to be delivered whether actually received or
        not when deposited in the United States Mail, postage prepaid, sent by
        federal express or other nationally recognized overnight courier,
        Certified or Registered Mail, return receipt requested, addressed to the
        parties hereto at the respective addresses set out below, or at other
        such addresses as they have heretofore specified by written notice
        delivered in accordance therewith.

        LANDLORD:

        Weeks Realty, L.P.
        1800 Perimeter Park Drive
        Suite 200
        Morrisville, North Carolina 27560
        Attention: Mr. Robert Cutlip

        With a copy to:

        Dave Lindner
        Weeks Corporation
        1800 Perimeter Park Drive
        Suite 200
        Morrisville, NC 27560

        and

        Cathy M. Rudisill, Esq.
        Smith Helms Mullis & Moore, L.L.P.
        2800 Two Hannover Square
        Raleigh, North Carolina 27601

        TENANT:

        Tekelec
        26580 West Agoura Road


                                       14


<PAGE>   18
         Calabasas, California 91302
         Attention: Gilles Godin

If and when included within the term "Landlord", as used in this instrument,
there is more than one person, firm or corporation, all shall jointly arrange
among themselves for their joint execution of such a notice specifying some
individual at some specific address for the receipt of notices and payments to
Landlord; if and when included within the term "Tenant", as used in this
instrument, there is more than one person, firm or corporation, all shall
jointly arrange among themselves for their joint execution of such a notice
specifying some individual at some specific address within the continental
United States for the receipt of notices to Tenant. All parties included within
the terms "Landlord" and "Tenant", respectively, shall be deemed to have
received notices in accordance with the provisions of this paragraph with the
same effect as if each had received such notice.

        21.     BROKER'S CLAUSE. Tenant warrants and represents to Landlord that
it has had no dealings with any real estate broker or agent in connection with
this Lease, and Tenant covenants to pay, hold harmless, and indemnify Landlord
from and against any and all costs, expenses, liabilities (including reasonable
attorneys' fees), causes of action, claims or suits in connection with any
compensation, commission, fee, or charges claimed by any other real estate
broker or agent with respect to this Lease or the negotiation thereof, arising
out of any act of Tenant. Landlord warrants and represents to Tenant that it has
had no dealings with any real estate broker or agent in connection with this
Lease, and Landlord covenants to pay, hold harmless, and indemnify Tenant from
and against any and all costs, expenses, liabilities (including reasonable
attorneys' fees), causes of action, claims or suits in connection with any
compensation, commission, fee, or charges claimed by any other real estate
broker or agent with respect to this Lease or the negotiation thereof, arising
out of any act of Landlord.

        22.     LANDLORD'S LIABILITY. Notwithstanding anything to the contrary
contained in this Lease, Tenant agrees and understands that Tenant shall look
solely to the estate and property of Landlord in the Building for the
enforcement of a judgment (or other judicial decree) requiring the payment of
money by Landlord to Tenant by reason of default or breach of Landlord in
performance of its obligations under this Lease, it being intended that there
will be absolutely no personal liability on the part of Landlord, its successors
and assigns with respect to any of the terms, covenants, and conditions of this
Leases, and no other assets of Landlord or of Landlord's partners, if any, shall
be subject to levy, execution, attachment or any other legal process for the
enforcement or satisfaction of the remedies pursued by Tenant in the event of
such default or breach, this exculpation of liability to be absolute and without
exception whatsoever.

        23.     RULES AND REGULATIONS. Tenant shall fully comply with the Rules
and Regulations attached hereto as Exhibit D and made a part hereof and any and
all modifications thereof or amendments thereto with respect to which Landlord
notifies Tenant and which are applied on a non-discriminatory basis to all
tenants in the building in which the Premises are located.

        24.     HAZARDOUS MATERIALS.

        (a) Tenant agrees that it will not release, discharge, place, hold, or
        dispose of any Hazardous Material (as hereinafter defined) on, under or
        at the Premises, in the Building, or on the Land, and that it will not
        use the Premises, the Building, the Land, or any other portion thereof
        as a treatment, storage, or disposal (whether permanent or temporary)
        site for any Hazardous Material. Tenant further agrees that it will not
        cause or allow any asbestos to be incorporated into any improvements or
        alterations which it makes or causes to be made to the Premises, or the
        Building.

        (b) Tenant hereby agrees to and does indemnify, defend and hold harmless
        Landlord from and against any and all losses, liabilities, damages,
        injuries, costs, expenses and claims of any and every kind whatsoever
        (including without limitation, court costs and attorneys' fees) which at
        any time or from time to time may be paid, incurred or suffered by, or
        asserted against Landlord for, with respect to, or as a direct or
        indirect result of (i) any breach by Tenant of the provisions of this
        Paragraph, or (ii) to the extent caused or


                                       15


<PAGE>   19
        allowed by Tenant or any agent, employee, invitee, or licensee of
        Tenant, the presence on or under, or the escape, seepage, leakage,
        spillage, discharge, emission, or release from, onto, or into the
        Premises, the Building, the Land, the atmosphere, or any watercourse,
        body of water, or groundwater, of any Hazardous Material (including,
        without limitation, any losses, liabilities, damages, injuries, costs,
        expenses or claims asserted or arising under the Comprehensive
        Environmental Response, Compensation and Liability Act, any so-called
        "Superfund" or "Superlien" law, or any other Federal, state, local or
        other statute, law, ordinance, code, rule, regulation, order or decree
        regulating, relating to or imposing liability or standards of conduct
        concerning any Hazardous Material); and the provisions of and
        undertakings and indemnification set forth in this paragraph shall
        survive the termination or expiration of this Lease, for any reason, and
        shall continue to be the liability, obligation and indemnification of
        Tenant, binding upon Tenant forever. The provisions of the preceding
        sentence shall govern and control over any inconsistent provision of
        this Lease.

        (c) For purposes of this Lease, "Hazardous Material" means and includes
        any hazardous or toxic substance, pollutant, contaminant, gas, or
        petroleum product defined as such in (or for purposes of) the
        Comprehensive Environmental Response, Compensation, and Liability Act,
        as amended, any so-called "Superfund" or "Superlien", law, the Toxic
        Substances Control Act, as amended, or any other Federal, state or local
        statute, law, ordinance, code, rule, regulation, order or decree
        regulating, relating to, or imposing liability or standards of conduct
        concerning, any hazardous, toxic or dangerous waste, substance or
        material, as now or at any time hereafter in effect, or any other
        hazardous, toxic or dangerous, waste, substance or material, gas or
        petroleum product.

        (d) Notwithstanding the foregoing, Tenant shall have the right to handle
        Hazardous Materials in the normal course of its business, provided,
        however, Tenant shall conduct all such activities in accordance with all
        applicable laws and regulations.

        25.     [INTENTIONALLY DELETED.]

        26.     COVENANT OF TENANT. If Landlord encounters difficulties in
        negotiating construction or permanent financing for the Premises, and
        after using its best efforts is unable to resolve those difficulties
        without obtaining minor modifications to this Lease, Tenant will act in
        good faith to work with Landlord in Landlord's efforts, but this
        agreement on the part of Tenant will not require Tenant to make any
        changes that in Tenant's reasonable judgment alter the term hereof, or
        adversely affect any substantive right or interest of Tenant, whether
        legal or economic.

        27.     MISCELLANEOUS.

        A.      Words of any gender used in this Lease shall be held and
        construed to include any other gender, and words in the singular number
        shall be held to include the plural, unless the context otherwise
        requires.

        B.      The terms, provisions and covenants and conditions contained in
        this Lease shall apply to, inure to the benefit of, and be binding upon
        the parties hereto and upon their respective heirs, legal
        representatives, successors and permitted assigns, except as otherwise
        herein expressly provided. Landlord shall have the right to assign any
        of its rights and obligations under this Lease. Each party agrees to
        furnish to the other, promptly upon demand, a resolution, or other
        appropriate documentation evidencing the due authorization of such party
        to enter into this Lease.

        C.      The captions inserted in this Lease are for convenience only and
        in no way define, limit or otherwise describe the scope or intent of
        this Lease, or any provision hereof, or in any way affect the
        interpretation of this Lease.

        D.      Tenant agrees from time to time, within ten (10) days after
        request of Landlord, to deliver to Landlord, or Landlord's designee, an
        estoppel certificate stating that this Lease is in full force and
        effect, the date to which rent has been paid, the unexpired term of this
        Lease and such other matters pertaining to this Lease as may be
        reasonably requested by Landlord. It is understood and agreed that
        Tenant's obligation to furnish such estoppel


                                       16


<PAGE>   20
        certificates in a timely fashion is a material inducement for Landlord's
        execution of this Lease.

        E.      This Lease may not be altered, changed or amended except by an
        instrument in writing signed by both parties hereto.

        F.      All obligations of Tenant and Landlord hereunder not fully
        performed as of the expiration or earlier termination of the term of
        this Lease shall survive the expiration or earlier termination of the
        term hereof, including, without limitation, all payment obligations
        concerning the condition of the Premises. Upon the expiration or earlier
        termination of the term hereof, and prior to Tenant's vacating the
        Premises, Tenant shall pay to Landlord any amount reasonably estimated
        by Landlord as necessary to put the Premises, including, without
        limitation, all heating and air conditioning systems and equipment
        therein, in good condition and repair. Tenant shall also, prior to
        vacating the Premises, pay to Landlord the amount, as estimated by
        Landlord, of Tenant's obligation hereunder for real estate taxes and
        insurance premiums for the year in which the Lease expires or terminates
        up to the Termination Date. All such amounts shall be used and held by
        Landlord for payment of such obligations of Tenant hereunder, with
        Tenant being liable for any additional costs therefor upon demand by
        Landlord, or with any excess to be returned to Tenant after all such
        obligations have been determined and satisfied, as the case may be. Any
        security deposit held by Landlord shall be credited against the amount
        payable by Tenant under this Paragraph 27(F).

        G.      In the event of a transfer by Landlord of its interest in the
        Premises, Landlord shall be released from all obligations and
        liabilities under the terms of this Lease subsequent to the date of such
        transfer. In the event a transferee shall agree to assume the
        obligations and liabilities of Landlord under the Lease prior to the
        date of the transfer, Landlord shall be released from all obligations
        and liabilities under the Lease.

        H.      If any clause or provision of this Lease is illegal, invalid or
        unenforceable under present or future laws effective during the term of
        this Lease, then and in that event, it is the intention of the parties
        hereto that the remainder of this Lease shall not be affected thereby,
        and it is also the intention of the parties to this Lease that in lieu
        of each clause or provision of this Lease that is illegal, invalid or
        unenforceable, there be added as a part of this Lease contract a clause
        or provision as similar in terms to such illegal, invalid or
        unenforceable clause or provision as may be possible and be legal, valid
        and enforceable.

        I.      [INTENTIONALLY DELETED.]

        J.      All references in this Lease to "the date hereof" or similar
        references shall be deemed to refer to the last date, in point of time,
        on which all parties hereto have executed this Lease.

        K.      Time is of the essence of this Lease.

        L.      Landlord shall not be in default in the performance of any of
        Landlord's obligations hereunder unless and until Landlord shall have
        failed to perform such duties or obligations within thirty (30) days (or
        such additional time as is reasonably required to correct any such
        default) after written notice by Tenant to Landlord, and to any
        mortgagee with a lien on the Land or the Building, properly specifying
        wherein Landlord has failed to perform any such duty or obligation.
        Neither party hereto shall have any liability to the other party hereto
        for any incidental, special, indirect, punitive, or consequential
        damages of a party hereto for any reason whatsoever.

        M.      In the event that Landlord shall default in the performance of
        Landlord's obligations hereunder, the holder of a mortgage or the
        beneficiary of a deed of trust which includes the Premises shall have
        the right, but not the obligation, to perform or comply with any
        covenants, agreements and provisions violated in connection with such
        default. Further, if such holder of beneficiary notifies Tenant that
        such holder or beneficiary has taken over Landlord's right under this
        Lease, Tenant shall not assert any right to deduct the cost of repairs
        or any monetary claims against Landlord theretofore accrued from rent


                                       17


<PAGE>   21
        thereafter due and payable, but shall look solely to Landlord and not
        such holder or beneficiary for satisfaction of such claim.

        N.      This Lease does not create the relationship of partner or joint
        venturer between Landlord and Tenant. This Lease shall not result in the
        creation of an estate for years in Tenant. Accordingly, Tenant shall
        have only an usufruct not subject to levy or sale. Tenant shall have no
        rights of assignment, subletting, sale or transfer beyond those set
        forth herein and hereby waives any such rights existing pursuant to the
        laws of the State of North Carolina or otherwise. No estate shall pass
        out of Landlord to Tenant hereunder, and Tenant shall not be entitled to
        any award of whatsoever nature based on this Lease and/or Tenant's right
        to occupy the Premises hereunder.

        O.      The laws of the State of North Carolina shall govern the
        interpretation, the validity, performance and enforcement of this Lease.

        P.      (i) If Tenant is a corporation, the undersigned officer of
        Tenant does hereby warrant and certify to Landlord that Tenant is a
        corporation in good standing and duly organized under the laws of the
        State of North Carolina, or if chartered in a state other than the State
        of North Carolina, is a corporation in good standing and duly organized
        under the laws of such state and is authorized to do business in the
        State of North Carolina. The undersigned officer of Tenant hereby
        further warrants and certifies to Landlord that such officer is
        authorized and empowered to bind the corporation to the terms of this
        Lease by such officer's signature hereto, (ii) If Tenant is a general or
        limited partnership, the undersigned general partner of Tenant does
        hereby warrant and certify to Landlord that Tenant is a general
        partnership or limited partnership, as the case may be, validly existing
        under the laws of the State of North Carolina, or if formed in a state
        other than the State of North Carolina, is a general partnership or
        limited partnership validly existing under the laws of such state and is
        authorized to do business in the State of North Carolina. The
        undersigned general partner of Tenant hereby further warrants and
        certifies to Landlord that such general partner is authorized and
        empowered to bind Tenant to the terms of this Lease by such general
        partner's signature hereto.

        Q.      This Lease shall be executed in duplicate, each of which shall
        be deemed an original and complete of itself and may be introduced into
        evidence or used for any purpose without the production of any other
        copy. If Tenant is a corporation, two authorized corporate officers must
        execute this Lease in their appropriate capacity for Tenant and affix
        the corporate seal.

        R.      The provisions contained in the Rider attached hereto, if any,
        are incorporated herein by reference and made a part of this Lease. In
        the event of a conflict between the printed portion of this Lease and
        the Rider, the provisions of the Rider shall govern and control.

        S.      Although the printed provisions of this Lease were drafted by
        Landlord, such fact shall not cause this Lease to be construed either
        for or against Landlord or Tenant.

        T.      This Lease may not be recorded. Upon the request and at the
        expense of Tenant, Landlord shall execute a memorandum of Lease suitable
        for recording which shall omit the financial terms herein but which
        shall identify the Premises and the term of this Lease, Upon the
        expiration of this Lease, a recorded memorandum of this Lease may be
        canceled of record by a document executed by Landlord, or its successor
        in interest for such purpose.

        U.      To the best of its knowledge, Landlord certifies that on or
        after January 1, 2000, all systems installed in the Building by or on
        behalf of Landlord to service the Premises, including, but not limited
        to, the heating, air conditioning, sprinkler, security, electrical,
        plumbing, and other systems installed by Landlord in the Building will
        record, store, process, and present calendar dates in the same manner
        and with the same functionality as such Systems record, store, process,
        and present calendar dates falling on or before December 31, 1999.


                                       18


<PAGE>   22
        V.      Tenant shall provide to Landlord within ninety days of the close
        of its fiscal year, and thereafter upon reasonable request of Landlord,
        financial statements of Tenant certified by the chief financial officer
        of Tenant, and Tenant shall act to ensure that any guarantor hereof
        provides Landlord with copies of its financial statements within ninety
        days of the close of its fiscal year.

        W.      No remedy conferred herein is intended to be exclusive of any
        other remedy and each and every remedy shall be cumulative and shall be
        in addition to every other remedy given hereunder or thereunder or now
        or hereafter existing at law or in equity or by statute or otherwise.

        X.      Parking shall be available for tenants of the Building at the
        rate of five parking spaces for each 1000 rentable square feet of the
        Building.

[THE REMAINDER OF THIS PAGE WAS INTENTIONALLY LEFT BLANK.]


                                       19


<PAGE>   23
        IN WITNESS WHEREOF, the parties hereto have executed this Lease under
seal as of the day and year first above written.

                        LANDLORD:

                        WEEKS REALTY, L.P. (SEAL), a 
                        Georgia limited partnership 
                        authorized to do business in the
                        State of North Carolina as
                        WEEKS REALTY LIMITED PARTNERSHIP

                        BY: WEEKS GP HOLDINGS, INC.,
                        Georgia corporation, its sole general partner

                        By:   /s/ ROBERT G. CUTLIP
                             -------------------------------
                             Robert G. Cutlip,
                             Senior Vice President



                        TENANT:

                        TEKELEC, a California
                        corporation

                        By:  /s/ GILLES C. GODIN      By:  /s/ MIKE MARGOLIS
                             -----------------------       ---------------------
                        Print Name: Gilles C. Godin   Print Name: Mike Margolis
                                  ------------------            ----------------
                        Vice President & CFO          President & CEO


Witness/Attest:


/s/ KAROLYN FLESHER
-------------------------------
Print Name: Karolyn Flesher
           --------------------           
Title: Assistant Secretary                
      -------------------------           

[CORPORATE SEAL]


                                       20



<PAGE>   24

                                   EXHIBIT A

                               LEGAL DESCRIPTION

        METES AND BOUNDS DESCRIPTION FOR PHASE 1 LOT 8 PARAMOUNT CENTER

That 15.86 acre tract of land lying in the Cedar Fork Township, Morrisville, 
Wake Country, North Carolina, and being a portion of the tract found in Deed 
Book (D.B.) 5605 Page (Pg.) 216-218 in the Register of Deeds office of said 
Wake County, and being bounded on the North by Lot 7 Paramount Center; on the 
East by J.A. Ferrell (D.B.) 1437 (Pg.) 780 now or formerly and Jesse Marcom 
(D.B.) 877 (Pg.) 32 now or formerly; on the South by Lot 9 Paramount Center and 
Proposed Paramount Parkway (100' Public right-of-way); and on the West by Phase 
II Paramount Center Lot 8 and Proposed Road "A" (100' Public right-of-way); and 
being more particularly described as follows:

Beginning at a new iron pipe set in the Western line of said J.A. Ferrell and
also being the Northeast corner of said Lot 8, said iron being South 03 degrees
05 minutes 47 seconds East 884.33 feet from an existing iron pipe in the said
Western line of J.A. Ferrell; thence along said J.A. Ferrell's Western line,
South 03 degrees 05 minutes 47 seconds East 399.39 feet to an existing iron
pipe, a common corner with said Jesse Marcom; thence along the said Jesse
Marcom's Western line, South 00 degrees 25 minutes 05 seconds East 286.92 feet
to a point, the Northeast corner of said Lot 9, thence leaving said Jesse
Marcom's Western line along a common lot line with said Lot 9, South 88 degrees
41 minutes 07 seconds West 442.57 feet to a point; thence with said common Lot 9
line, South 51 degrees 26 minutes 44 seconds West 399.66 feet to a point in the
Northern right-of-way line of said proposed Paramount Parkway; thence along the
said Northern right-of-way line of Paramount Parkway Northwesterly 248.90 feet
along a nontangential curve to the left, central angle 14 degrees 19 minutes 57
seconds, radius 995.00 feet to a point; thence leaving said Northern
right-of-way line along a Phase line for Phases I and II, North 19 degrees 40
minutes 36 seconds East 114.00 feet to a point; thence North 00 degrees 00
minutes 00 seconds East 56.74 feet to a point; thence South 90 degrees 00
minutes 00 seconds East 195.69 feet to a point; thence Northeasterly 38.27 feet
along a tangential curve to the left, central angle 90 degrees 00 minutes 00
seconds, radius 25.00 feet to a point; thence North 00 degrees 00 minutes 00
seconds East 322.48 feet to a point; thence South 90 degrees 00 minutes 00
seconds West 36.51 feet to a point; thence North 00 degrees 00 minutes 00
seconds East 250.34 feet to a point; thence South 90 degrees 00 minutes 00
seconds West 141.35 feet to a point; thence North 48 degrees 14 minutes 55
seconds West 61.24 feet to a point in the Eastern right-of-way line of said
proposed Road "A"; thence along the said Eastern right-of-way line of Road "A:,
North 41 degrees 45 minutes 05 seconds East 385.98 feet to a new iron pipe set,
the Northwest corner of said Lot 8 and common corner with said Lot 7; thence
leaving said Eastern right-of-way line with the common line of said Lot 7, South
57 degrees 37 minutes 22 seconds East 369.41 feet to a new iron pipe set; thence
with the common line of said Lot 7, South 80 degrees minutes 30 seconds 357.55
feet to the Point of Beginning.

Said parcel contains 15.86 acres and is the same as shown in a Preliminary Site 
Plans entitled "PARAMOUNT CENTER - LOT 8" prepared by DSAtlantic Corporation 
and dated May 20, 1998 with a last revision date of August 15, 1998.


<PAGE>   25

                                                                       EXHIBIT B
                                                                                
                                                                      FLOOR PLAN



TEKELEC BUILD TO SUIT

PARAMOUNT CENTER
MORRISVILLE, NORTH CAROLINA
FIRST FLOOR






                                  [FLOOR PLAN]
<PAGE>   26

                                                                     EXHIBIT B-1
                                                                                
                                                              FLOOR PLAN (cont.)



TEKELEC BUILD TO SUIT

PARAMOUNT CENTER
MORRISVILLE, NORTH CAROLINA
SECOND FLOOR






                                  [FLOOR PLAN]
<PAGE>   27
                                   EXHIBIT C

                            PLANS AND SPECIFICATIONS

             [TO BE ATTACHED UPON APPROVAL BY LANDLORD AND TENANT]
<PAGE>   28
                                  EXHIBIT C-1

                                    SCHEDULE
<PAGE>   29
<TABLE>
<S>  <C>    <C>                                                     <C>                   <C>
                                      TEKELEC INTERIOR DESIGN PROGRAM
---------------------------------------------------------------------------------------------------------------

10          Task Name                                               Duration              Start
---------------------------------------------------------------------------------------------------------------
 1          TEKELEC PRELIMINARY SCHEMATIC SUBMITTAL                 0 days                10/16/98

---------------------------------------------------------------------------------------------------------------
 2          TEKELEC WEEKS PRELIMINARY SCHEMATIC REVIEW              5 days                10/19/98

---------------------------------------------------------------------------------------------------------------
 3          REVISE PRELIMINARY SCHEMATIC PER COMMENTS               3 days                10/26/98

---------------------------------------------------------------------------------------------------------------
 4          FINAL APPROVED PRELIMINARY SCHEMATIC ISSUED             0 days                10/28/98

---------------------------------------------------------------------------------------------------------------
 5

---------------------------------------------------------------------------------------------------------------
 6          WEEKS SUBMITS CORE FINISHES FOR APPROVAL                0 days                10/28/98

---------------------------------------------------------------------------------------------------------------
 7          TEKELEC REVIEWS SELECTIONS                              5 days                10/29/98

---------------------------------------------------------------------------------------------------------------
 8          WEEKS REVISES CORE FINISHES, IF NECESSARY               3 days                11/5/98

---------------------------------------------------------------------------------------------------------------
 9          WEEKS PRESENTS FINAL CORE FINISHES                      1 day                 11/10/98

---------------------------------------------------------------------------------------------------------------
10

---------------------------------------------------------------------------------------------------------------
11          TEKELEC PRODUCES "FOR PRICING" DRAWINGS                 10 days               10/29/98

---------------------------------------------------------------------------------------------------------------
12          TEKELEC SUBMITS "FOR PRICING" DRAWINGS                  0 days                11/11/98

---------------------------------------------------------------------------------------------------------------
13          WEEKS REVIEWS PRICING DOCUMENT FOR CLARITY              3 days                11/12/98

---------------------------------------------------------------------------------------------------------------
14          TEKELEC REVISES DOCUMENTS PER COMMENTS                  2 days                11/17/98

===============================================================================================================
Schedule Date: 6/3/97           Task [             ]      Critical Task [                ]         Milestone  *
Price Date: 9/1/98
tekelec.mpp
---------------------------------------------------------------------------------------------------------------
                                                     Page 1
---------------------------------------------------------------------------------------------------------------


---------------------------------------------------------------------------------------------------------------------------
   Jul '98    Aug '98      Sep '98    Oct '98    Nov '98      Dec '98    Jan '99       Feb '99    Mar '99    Apr '99    May
28 5 12 19 26 2 9 16 23 30 6 13 20 27 4 11 18 25 1 8 15 22 29 6 13 20 27 3 10 17 24 31 7 14 21 28 7 14 21 28 4 11 18 25 2 9
---------------------------------------------------------------------------------------------------------------------------

                                      10/16 * TEKELEC PRELIMINARY SCHEMATIC SUBMITTAL
---------------------------------------------------------------------------------------------------------------------------
                           TEKELEC/ WEEKS PRELIMINARY SCHEMATIC REVIEW
                                           10/19 [ ] 10/23
---------------------------------------------------------------------------------------------------------------------------
                              REVISE PRELIMINARY SCHEMATIC PER COMMENTS
                                          10/26 [ ] 10/28

                                            10/28 * FINAL APPROVED PRELIMINARY SCHEMATIC ISSUED
---------------------------------------------------------------------------------------------------------------------------


---------------------------------------------------------------------------------------------------------------------------

                                            10/28 * WEEKS SUBMITS CORE FINISHES FOR APPROVAL
---------------------------------------------------------------------------------------------------------------------------
                                      TEKELEC REVIEWS SELECTIONS
                                             10/29 [ ] 11/4
---------------------------------------------------------------------------------------------------------------------------
                                 WEEKS REVISES CORE FINISHES, IF NECESSARY
                                                11/5 [ ] 11/9
                                    WEEKS PRESENTS FINAL CORE FINISHES
                                                11/10 [ ] 11/10
---------------------------------------------------------------------------------------------------------------------------


---------------------------------------------------------------------------------------------------------------------------
                                TEKELEC PRODUCES "FOR PRICING" DRAWINGS
                                             10/29 [   ] 11/11


                                                   11/11 * TEKELEC SUBMITS "FOR PRICING" DRAWINGS
---------------------------------------------------------------------------------------------------------------------------
                                     WEEKS REVIEWS PRICING DOCUMENT FOR CLARITY
                                                    11/12 [ ] 11/16
                                         TEKELEC REVISES DOCUMENTS PER COMMENTS
                                                     11/17 [ ] 11/18
===========================================================================================================================
       Summary [                ]                                                                  TENANT APPROVED
                                                                                                   BY /s/ [Sig Illegible]
                                                                                                   DATE 9/2/98
---------------------------------------------------------------------------------------------------------------------------
                                                         Page 1
---------------------------------------------------------------------------------------------------------------------------
                                                                                                                Page 1 of 3
</TABLE>
<PAGE>   30
                        TEKELEC INTERIOR DESIGN PROGRAM

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
                                                               Jul '98       Aug '98      Sep '98     Oct '98    Nov '98   Dec '98
                                                            ------------------------------------------------------------------------
ID  i   TASK NAME                          DURATION  START  28 5 12 19 26 2|9 16;23 30 6 13|20|27 4 11 18 25 1 8 15|22 29 6 13 20 27
------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C>                                 <C>       <C>   <C>
15      WEEKS PRICING OF DOCUMENTS         15 DAYS  11/19/98
-------------------------------------------------------------
16      PRICING PRESENTED TO TEKELEC        0 days   12/9/98
-------------------------------------------------------------
17
-------------------------------------------------------------
18
-------------------------------------------------------------
19      TEKELEC REVIEW OF PRICING DATA      5 days 12/10/98
-------------------------------------------------------------
20      WEEKS REPRICE PER TEKELEC COMMENTS  5 days 12/17/98
-------------------------------------------------------------
21      TEKELEC SIGN-OFF OF FINAL "WORK"
        COST                                0 days 12/23/98
-------------------------------------------------------------
22      FINAL "FOR CONSTRUCTION" DRAWING
        PRODUCED                           17 days 12/24/98
-------------------------------------------------------------
23
-------------------------------------------------------------
24      INTERIOR BUILDING PERMIT           23 days  1/18/99
-------------------------------------------------------------
25        INITIAL SUBMISSION TO CITY        0 days  1/18/99
-------------------------------------------------------------
26        CITY REVIEW AND COMMENT          15 days  1/19/99
-------------------------------------------------------------
27        RECEIVE COMMENTS                  0 days   2/8/99
-------------------------------------------------------------
28        ADDRESS COMMENTS                  3 days  2/29/99
------------------------------------------------------------------------------------------------------------------------------------
Schedule Date: 6/3/97        Task [ ]        Critical        Task [ ]        Milestone [ ]        Summary [ ]
Print Date: 9/1/98
Tekelec.mpp
------------------------------------------------------------------------------------------------------------------------------------
                                                        Page 2
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>


<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------------------------------
                                                               Jan '99        Feb '99      Mar '99     Apr '99      May '99
                                                            ------------------------------------------------------------------------
ID  i   TASK NAME                          DURATION  START   3  10  17  24  31  7  14  21  28  7  14  21  28  4  11  18  25  2  9
------------------------------------------------------------------------------------------------------------------------------------
<S> <C> <C>                                 <C>       <C>   <C>
15      WEEKS PRICING OF DOCUMENTS         15 DAYS  11/19/98          WEEKS PRICING OF DOCUMENTS
-------------------------------------------------------------         11/19 [ ] 12/9
16      PRICING PRESENTED TO TEKELEC        0 days   12/9/98
-------------------------------------------------------------          12/9 [ ] PRICING PRESENTED TO TEKELEC
17
-------------------------------------------------------------
18
-------------------------------------------------------------
19      TEKELEC REVIEW OF PRICING DATA      5 days 12/10/98           TEKELEC REVIEW OF PRICING DATA
-------------------------------------------------------------         12/10 [ ] 12/16   
20      WEEKS REPRICE PER TEKELEC COMMENTS  5 days 12/17/98
-------------------------------------------------------------         WEEKS REPRICE PER TEKELEC COMMENTS 
21      TEKELEC SIGN-OFF OF FINAL "WORK"                              12/17 [ ] 12/23
        COST                                0 days 12/23/98           12/23 [ ] TEKELEC SIGN-OFF OF FINAL "WORK" COST
-------------------------------------------------------------         FINAL "FOR CONSTRUCTION" DRAWING PRODUCED
22      FINAL "FOR CONSTRUCTION" DRAWING                              12/24 [ ] 1/18
        PRODUCED                           17 days 12/24/98           INTERIOR BUILDING PERMIT
-------------------------------------------------------------         1/18 [ ] INITIAL SUBMISSION TO CITY
23                                                                    CITY REVIEW AND COMMENT
------------------------------------------------------------          1/19 [ ] 2/8
24      INTERIOR BUILDING PERMIT           23 days  1/18/99           
-------------------------------------------------------------         2/8 [ ] RECEIVE COMMENTS
25        INITIAL SUBMISSION TO CITY        0 days  1/18/99           ADDRESS COMMENTS
-------------------------------------------------------------         2/9 [ ] 2/11
26        CITY REVIEW AND COMMENT          15 days  1/19/99
-------------------------------------------------------------
27        RECEIVE COMMENTS                  0 days   2/8/99
-------------------------------------------------------------
28        ADDRESS COMMENTS                  3 days  2/29/99
------------------------------------------------------------------------------------------------------------------------------------
Schedule Date: 6/3/97        Task [ ]        Critical        Task [ ]        Milestone [ ]        Summary [ ]
Print Date: 9/1/98
Tekelec.mpp
------------------------------------------------------------------------------------------------------------------------------------
                                                        Page 2
------------------------------------------------------------------------------------------------------------------------------------
</TABLE>
<PAGE>   31
                        TEKELEC INTERIOR DESIGN PROGRAM

<TABLE>

<S>    <C>    <C>                 <C>           <C> 
--------------------------------------------------------------
                                            
1D      i      Task Name          Duration        Start  
--------------------------------------------------------------
29            CITY FINAL REVIEW   5 days          21/12/99
--------------------------------------------------------------
30            RECEIVE PERMIT      0 days          2/18/99
--------------------------------------------------------------
</TABLE>

<TABLE>
<S>            <C>         <C>        <C>          <C>         <C>        <C>          <C>             <C>        <C>       <C>   
----------------------------------------------------------------------------------------------------------------------------------
Jul '98        Aug '98     Sep '98    Oct '98       Nov '98    Dec '98    Jan '99       Feb '99         Mar '99    Apr '99   May?
----------------------------------------------------------------------------------------------------------------------------------
28 5 12 19 25  2 9 16 23  30:6 13:20 27 4 11 18 25  1 8 15 22  29:6 13 20 27:3 10 17 24 31 7 14 21:26 7 14 21 28 4 11:18 25 2 9
----------------------------------------------------------------------------------------------------------------------------------
                                                                                CITY FINAL REVIEW
                                                                                 2/12 [ ]   2/18
                                        
          
                                                                                2/18  [ ]  RECEIVE PERMIT
-----------------------------------------------------------------------------------------------------------------------------------








Schedule Date: 6/3/97              Task           Critical Task            Milestone [ ]            Summary ________________
Print Date: 9/1/98
Tekelec.mpp
----------------------------------------------------------------------------------------------------------------------------------
                                     Page 3
----------------------------------------------------------------------------------------------------------------------------------
</TABLE>


                                  Page 3 0f 3



<PAGE>   32
                                  EXHIBIT C-2

                                DESIGN CRITERIA

DESIGN CRITERIA:

     A,   CONCRETE SYSTEMS

          1.   FOUNDATIONS

               a.   Spread Footings

                    i.   Provide at column line intersections, sized by 
               registered structural engineer designs.

                    ii.  Reinforced as required.

               b.   Perimeter Strip Footings

                    i.   Provide for exterior dock wall, sized by registered 
               structural engineer design.

                    ii.  Reinforced as required.

          2.   SLAB-ON-GRADE

               a.   4" thick; 3,000 psi concrete with 8 mil. vapor barrier on 
               compacted earth.

               b.   Provide perimeter turndown for exterior walls at slab edge, 
               reinforced as required.

               c.   Include 1.5" thick by 3' wide rigid insulation underslab on 
               grade at exterior walls, per local energy codes.

               d.   Provide clear sealed floor finish on prepared surface.

          
          3.   ELEVATED SLAB

               a.   Provide 3,000 psi lightweight concrete on galvanized 
               composite metal deck, reinforced with 6x6 W2.1x2.1 welded wire 
               mesh.

     B.   MASONRY

          1.   BRICK VENEER

               a.   Modular brick veneer with 3/8" thick mortar joint.

               b.   Field brick material: Richtex, #760 Medium Gray Wirecut.

               c.   Accent brick material: Lee Brick, #608, Beauford.

               d.   Mortar: Natural gray.

          2.   MISCELLANEOUS

               a.   Two-part, screw-attached ties at exterior sheathing 
               construction.

               b.   Thru-wall flashing.
<PAGE>   33
          c.   Include weep wicks to conduct moisture out of walls as noted on 
          contract documents.

     C.   METALS

          1.   STRUCTURAL STEEL

               a.   Provide a free standing structural steel frame.

               b.   Floor to floor height: 14'.

          2.   MISCELLANEOUS METALS

               a.   Include five interior concrete filled metal pan steel 
               stairs.

               b.   Include brick shelf angle and kickers.

               c.   Include elevator pit ladders, sump angle frames and sills.

               d.   Include pipe bollards at loading dock.

          3.   ARCHITECTURAL METALS

               a.   Include steel picket handrail at second floor lobby.

     D.   CARPENTRY

          1.   ROUGH CARPENTRY

               a.   Include pressure-treated wood nailers for roofing system.

               b.   Include pressure-treated wood nailers for storefront system.

               c.   Include interior wood blocking at core areas.

          2.   MILLWORK

               a.   Include solid surface lavatories at core area restrooms.

     E.   MOISTURE PROTECTION

          1.   CAULKING

               a.   Include dymeric caulking of masonry control joints.

               b.   Include caulking of window wall and storefront systems.

               c.   Include caulking of hollow metal exterior door frames.

          2.   ROOF SYSTEMS

               a.   Type: single-ply, river-stone ballasted, 45 mil. E.P.D.M.
               membrane system on one (1) layer of 5/8" gypsum board, with a
               20-year warranty on materials and 10-year warranty on
               installation.

               b.   Insulation: R-14 rigid insulation.

               c.   Include 24-gauge, pre-finished Kynar 500 coping, flashing,
               downspouts and gutters.


                                                                               2
<PAGE>   34
     3.   FIREPROOFING

          a.   Include sprayed on fireproofing to provide 1 hour rating to the
          floor, columns and bracing.

     4.   SKYLIGHT STRUCTURE

          a.   Provide one pyramid skylight structure, with translucent
          fiberglass and glass panels.

F.   DOORS & WINDOWS

     1.   WOOD DOORS

          a.   Include 3' x 8'-8" custom-grade, solid core, rotary sliced
          natural birch wood doors in hollow metal frames.

          b.   Include rated doors with positive latch set and closers as
          required in rated wall assemblies.

          c.   Include doors for core area only. All other doors to be included
          in the Office Finish Allowance.

     2.   FINISH HARDWARE

          a.   Include finish hardware.

     3.   STOREFRONT

          a.   Include system consisting of 1" Ford Blue, insulated, reflective
          glass in a prefinished Kawneer frame.

          b.   Include aluminum Kawneer 1500 series curtainwall system at front
          entry.

          c.   Include medium stile glass entry doors, with manufacturer's
          standard hardware.

          d.   Finish of exposed aluminum surfaces to be clear anodized.

G.   FINISHES

     1.   DRYWALL CONSTRUCTION

          a.   Exterior wall: metal studs with gypsum board sheathing, 15 lb.
          felt, brick ties and flashing.

          b.   Partition wall: metal studs with gypsum board, attached to metal
          ceiling grid and supported to structure as required.

          c.   Elevator wall: metal studs with fire rated gypsum liner panel on
          one side and fire rated GWB on opposite side.

          d.   Stair walls: metal studs with fire rated GWB on each side.

          e.   Typical core walls: metal studs with gypsum board and sound batt
          insulation. Walls to be one-hour fire rated as required by code.

          f.   All other partitions and furring is included in the Office Finish
          Allowance.

     2.   ACOUSTICAL CONSTRUCTION


                                                                               3


<PAGE>   35
          a.   Core area ceilings: Provide USG 2'-0" x 2'-0" #707 Glacier
          acoustical ceiling furnished and fully installed.

          b.   Tenant ceilings: Provide 2'-0" x 4'-0" framed grid with Armstrong
          Cortega revealed #704 acoustical tile stocked on floor.

     3.   TILE

          a.   Provide 2" x 2" unglazed ceramic floor tile and base, in each
          toilet.

          b.   Well walls in toilets to receive 4-1/4" x 4-1/4" bright/matte
          wall tile and trim, to 5'-0" af.f.

          c.   Provide quarry tile at the entry lobby.

     4.   CARPET AND RESILIENT FLOORING

          a.   Provide an allowance of $20.00/SY for the furnishing and
          installation of carpet.

          b.   Carpet to be utilized in core areas.

          c.   Provide 12" x 12" x 1/8" VCT in the freight elevator lobbies.

          d.   Mechanical, electrical, phone and elevator equipment rooms to
          have an exposed concrete floor.

          e.   Provide 4" rubber cove base.

          f.   All areas outside of the core area are included in the Finish
          Allowance.

     5.   PAINTING AND WALLCOVERING

          a.   Provide flat latex paint for the interior of the stairwells,
          freight elevator lobby, mechanical room, electrical room, phone room
          and elevator equipment room.

          b.   Provide alkyd enamel painting of metal pan stairs and rails.

          c.   Provide fabric wallcovering in the lobby area.

          d.   Provide vinyl wallcovering in the restrooms.

          e.   All areas outside of core area are included in the Finish
          Allowance.

H.   SPECIALTIES

     1.   TOILET PARTITIONS

          a.   Provide baked enamel steel, floor mounted, overhead braced toilet
          partitions.

          b.   Provide baked enamel steel, wall hung, urinal screens.

     2.   TOILET ACCESSORIES

          a.   Provide accessories in men's toilets as follows:

               i.   Paper towel dispenser and waste receptacle - Bobrick 3944.

               ii.  Double-roll toilet tissue holder - Bobrick 2740.


                                                                               4
<PAGE>   36
            iii. Soap dispenser - Bobrick 822.

            iv.  Grab bar B6806 X 36"

            v.   Grab bar B6806 X 42"

        b.  Provide accessories in women's toilet as follows:

            i.   Paper towel dispenser and waste receptacle - Bobrick 3944.

            ii.  Double-roll toilet tissue holder - Bobrick 2740.

            iii. Soap dispenser - Bobrick 822.

            iv.  Grab bar B6806 x 36"

            v.   Grab bar B6806 x 42"

            vi.  Napkin-tampon disposal - Bobrick B822.

        c.  Provide mop and broom rack in each janitor closet.

    3.  DOCK BUMPERS

        a.  Provide dock bumpers at loading dock.

    4.  BLINDS

        a.  Provide 1" horizontal mini-blinds on exterior windows.

    5.  ELEVATORS

        a.  Provide two (2), 2500 lb. capacity, 125 fpm holeless hydraulic
            passenger elevators.

        b.  Provide one (1), 4500 lb. capacity, 100 fpm holeless hydraulic 
            elevator.

        c.  Include an allowance of $10,000 per passenger cab for interior 
            finishes.

        d.  Freight elevator cab finishes to be manufacturer's standard.

I.  MECHANICAL

    1.  FIRE PROTECTION

        a.  Include a wet pipe sprinkler system per the approval of all 
        required local governing authorities.

        b.  System to be designed for Light Hazard Occupancy and hydraulically
        calculated to meet a design density of 0.10 gallons per minute over
        the most remove 1,500 SF.

        c.  Provide maximum head spacing of 225 SF.

        d.  Provide semi-recessed pendant heads with chrome escutcheons.

    2.  HEATING, VENTILATION AND AIR CONDITIONING (HVAC)



                                                                               5
<PAGE>   37
          a.   HVAC through VAV roof top units.

          b.   All medium pressure duct will be installed.

          c.   All components of the HVAC system "upstream" of terminal units 
          will be installed.

          d.   All components "downstream" from the terminal units will be part 
          of the tenant costs.

          e.   Conditioned air will be supplied to the occupied spaces via a
          Variable Air Volume (VAV) Air Conditioning System thermostatically
          controlled from individual zones within each tenant's suite. Each zone
          will have a thermostat and will not exceed 1,200 SF. All corners,
          exterior exposures, large conference rooms, training rooms, and
          elevator equipment rooms will constitute a zone and will have a
          thermostat. Other area requiring special zoning consideration will be
          considered above and beyond zoning provided and will be addressed
          prior to design.

          f.   The air conditioning system will be designed to maintain space
          temperature of 75 degrees F in the summer and a minimum space
          temperature of 68 degrees F in the winter. ASHRAE 1% (99%) weather
          data will determine the outside design conditions used for load
          calculations. Also, the following internal heat gain will be assumed
          for load calculations:

                    Occupancy load      =  1 person per 150 SF
                    Lighting load       =  2 watts per SF
                    Other electric load =  2 watts per SF

          A minimum of 1 cfm per SF of conditioned supply air will be provided.
          Outside air will be supplied to the space per standards set forth by
          ASHRAE 62-1989, but not less than 20 cfm per person.

          g.   The air conditioning system will be controlled via a central
          control panel with modem and terminal. All controls will be DDC
          (Direct Digital Control). Zone sensors (thermostats) will have
          thumbwheel control between pre-determined setpoints and override
          capability. Automatic shut-down of the air handling units will be
          provided per Standard Mechanical Code. As required, stairwell
          pressurization and elevator shaft smoke removal controls will be
          provided per Standard Mechanical Code and Standard Building Code.

          h.   The Atrium shall be provided with a code required smoke exhaust
          system, via two exhaust fans.

J.   PLUMBING

     1.   System shall include all core area fixtures, risers, floor drains,
     roof drains and all associated piping. One (1) 20 gallon, 3kW, electric
     water heater shall be provided for each core restroom group.

K.   ELECTRICAL SYSTEMS  

     1.   ELECTRICAL DISTRIBUTION

          a.   Provide 3,000 amp, 480/277 volt, main switchboard.

          b.   Electrical service will be distributed to sub-panels in the 
          electrical room in each quadrant on each floor, as follows:

               i.   277/480 volt, 400 amp panelboard for mechanical equipment

               ii.  277/480 volt, 100 amp panelboard for lighting

                                                                               6



<PAGE>   38
               iii. 120/208 volt, 2 section, 250 amp, 84 pole panelboard served 
                    from a 480:208/120 volt, 75 kva transformer

          c.   An allowance of 2 watts per square foot is to be provided on 
          each floor for lighting and approximately 5 watts per square foot 
          for 208/120 volt receptacles.

     2.   EMERGENCY DISTRIBUTION
     
          a.   Provide emergency battery lighting for all public areas and 
          corridors.

     3.   TELEPHONE SYSTEM

          a.   Provide (4) 4" underground conduits from the telephone company
          manhold at the property line to the main telephone room. 4'x8'
          telephone backboards shall be provided in each electrical room on each
          floor with (2) 4" conduit to each quadrant riser from the main
          telephone backboard.


     4.   LIGHTING

          a.   Fluorescent strip lighting shall be used in all storage areas and
          equipment rooms.

          b.   Tenant area fluorescent fixtures will be stacked on the floor and
          ready to be installed. Fixtures shall be 2'x4' three lamp, 3" deep
          parabolic lens (one per 100 useable square feet). Each fixture shall
          have air return features.

          c.   All fluorescent fixtures shall utilize electronic ballast's and
          T8 lamps with 3500K color.

          d.   Provide decorative lighting in each lobby.

          e.   Provide PL downlights to product 30 foot-candles in core toilets
          and corridors.

     5.   LIFE SAFETY SYSTEMS
          a.   A complete addressable fire alarm and life safety system shall be
          provided, including pull stations, smoke detectors, flow switches,
          horns, annunciator panel and control panel. Smoke detectors shall be
          provided in mechanical supply and return ducts, Electrical Room,
          Mechanical rooms and elevator lobbies.

     6.   BRANCH CIRCUIT DISTRIBUTION

          a.   Lighting

               i.   One 20 amp, 277 volt circuit per column bay with three
               circuits per homerun junction box will be provided.

          b.   Receptacle Circuits

               i.   One (1) one inch (1") conduit per bay will be provided.

L.   OFFICE FINISHES

     1.   To be provided by Weeks to Tekelec at later date

M.   EXCLUSIONS



                                                                               7

<PAGE>   39
          1.   The following is not included:

                 i. Security System.

                ii. Telephone/Data wiring.

               iii. 24 hour cooling or computer room units.

                iv. Dust collection systems.





                                                                               8
<PAGE>   40
                                   EXHIBIT D

                             RULES AND REGULATIONS

     1.   The sidewalks, common areas, and public portions of the Building, 
such as entrances, passages, courts, elevators, vestibules, stairways, 
corridors or halls, and the streets, alleys or ways surrounding or in the 
vicinity of the Building shall not be obstructed by Tenant, even temporarily, 
or encumbered by Tenant or used for any purpose other than ingress to and 
egress from the Premises.

     2.   No awnings or other projections shall be attached to the outside 
walls of the Building.

     3.  No sign, advertisement, notice or other lettering shall be exhibited, 
inscribed, painted or affixed by Tenant on any part of the outside of the 
Premises or Building unless approved by Landlord. Signs on entrance doors 
shall, at Tenant's expense, be inscribed, painted or affixed for each tenant by 
sign makers approved by Landlord. In the event of the violation of the 
foregoing by Tenant, Landlord may remove same without notice to Tenant or any 
liability therefor, and may charge the expense incurred by such removal to 
Tenant.

     4.  The sashes, sash doors, skylights, windows, heating, ventilating and 
air conditioning vents and doors that reflect or admit light and air into the 
halls, passageways or other public places in the Building shall not be covered 
or obstructed by Tenant.

     5.  No show cases or other articles shall be put in front of or affixed to
any part of the exterior of the Building, nor placed in the public halls,
corridors, or vestibules without the prior written consent of Landlord.

     6.  The bathrooms and plumbing fixtures shall not be used for any purposes 
other than those for which they were designed, and no sweepings, rubbish, rags, 
or other substances shall be thrown therein. All damages resulting from any 
misuse of the bathrooms or fixtures shall be the responsibility of Tenant.

     7.  Tenant shall not in any way deface any part of the Premises or the 
Building.

     8.  No bicycles, vehicles, or animals of any kind shall be brought into 
or kept in our about the Premises, or in the Building. No cooking shall be done 
or permitted by Tenant on the Premises except in conformity with all applicable 
laws, statutes, regulations and ordinances and then only in the area designated 
as a kitchen, if any, on the Premises of Tenant, which is to be primarily used 
by Tenant's employees for heating beverages and light snacks, and in the 
cafeteria. Tenant shall not cause or permit any unusual or objectionable odors 
to be produced upon or permeate from the Premises.

     9.  [INTENTIONALLY DELETED.]

     10. No space in the Building shall be used for the sale of merchandise, 
goods, or property of any king at auction except for food items sold in the 
cafeteria located on the Premises.

     11. Tenant shall not make, or permit to be made, any unseemly or 
disturbing noises or disturb or interfere with occupants of the Building or 
neighboring buildings or premises or those having business with them, whether 
by the use of any musical instrument, radio, talking machine, unmusical noise, 
whistling, singing, or in any other way. Tenant shall not throw anything out of 
the doors, windows or skylights or down the passageways


     12. Neither Tenant, nor any of Tenant's servants, employees, agents, 
visitors, or licensees, shall at any time bring or keep upon the Premises any 
inflammable, combustible or explosive fluid, or chemical substance, other than 
reasonable amounts of cleaning fluids or solvents required in the normal 
operation of Tenant's business offices.

     13. No additional locks or bolts of any kind shall be placed upon any of 
the doors, walls, accessways, or windows by  Tenant, nor shall any changes be 
made in existing locks or the


<PAGE>   41
mechanism thereof, without the prior written approval of Landlord and unless 
and until a duplicate key or access card, as applicable, is delivered to 
Landlord. Tenant shall, upon the termination of its tenancy (i) return to 
Landlord all keys for the Premises and for any area of the Building, or common 
areas, either furnished to, or otherwise procured by Tenant, (ii) restore the 
locks, walls, accessways, windows, and doors to their original condition on the 
date of this Lease by removing any security measures installed by Tenant, 
repairing any damage to the Premises or to the Building as a result of the 
restoration and removal, and (iii) in the event of the loss of any keys 
furnished to Tenant by Landlord, Tenant shall pay to Landlord the cost thereof.

     14. Tenant shall not overload any floor.

     15. Tenant shall not occupy or permit any portion of the Premises to be 
used for the possession, storage, manufacture or sale of liquor, narcotics, or 
tobacco in any form.

     16. Tenant shall be responsible for all persons for whom it issues passes 
and/or keys and shall be liable to Landlord for all acts of such persons.

     17. The Premises shall not be used for lodging or sleeping or for any 
immoral or illegal purpose.

     18. The requirements of Tenant will be attended to only by Landlord or the 
property manager of the Premises.

     19. Canvassing, soliciting, and peddling in the Building are prohibited 
and Tenant shall cooperate to prevent the same.

     20. All paneling, and other wood products not considered furniture shall 
be of fire retardant materials.

     21. No smoking is permitted in the Premises, or in the Building. Smoking 
is permitted outside the Building in designated smoking areas. All cigarette 
butts and other refuse should be placed in designated containers.

     22. No weapons concealed or visible are permitted in the Premises, in the 
Building, or on the Land.

     23. Landlord shall not be responsible to Tenant or liable for the 
non-observance or violation of any of these Rules and Regulations by any other 
tenant.

     Whenever the above rules conflict with any of the rights or obligations of 
Tenant pursuant to the provisions of the Lease, the provisions of the Lease 
shall govern.

<PAGE>   42
                                   EXHIBIT E

                               ADJACENT PROPERTY


That 8.50 acre tract of land lying in the Cedar Fork Township, Morrisville, Wake
County, North Carolina, and being a portion of the tract found in Deed Book
(D.B.) 5605 Page (Pg.) 216-218 and Book of Maps (BOM) 1998 (Pg.) 1232 in the
Register of Deeds office of said Wake County, and being bounded on the North 
and East by Phase I Lot 8 Paramount Center; on the South by Proposed Paramount 
Parkway (100' Public right-of-way); and on the West by Proposed Road "A" (100' 
Public right-of-way); and being more particularly described as follows:

Beginning at a point in the Northern right-of-way line of said proposed 
Paramount Parkway and also being South 41 degrees 45 minutes 05 seconds West 
385.98 feet from an existing iron pipe, the Northwest corner of said Lot 8; 
thence leaving said Northern right-of-way line along a Phase line for Phases I 
and II, South 48 degrees 14 minutes 55 seconds East 61.24 feet to a point; 
thence North 90 degrees 00 minutes 00 seconds East 141.35 feet to a point; 
thence South 00 degrees 00 minutes 00 seconds East 250.34 feet to a point; 
thence North 90 degrees 00 minutes 00 seconds East 36.51 feet to a point; 
thence South 00 degrees 00 minutes 00 seconds East 322.48 feet to a point; 
thence Southwesterly 39.27 feet along a tangential curve to the right, central 
angle 90 degrees 00 minutes 00 seconds, radius 25.00 feet to a point; thence 
North 90 degrees 00 minutes 00 seconds West 195.69 feet to a point; thence 
South 00 degrees 00 minutes 00 seconds West 56.74 feet to a point; thence 
South 19 degrees 40 minutes 36 seconds West 114.00 feet to a point in the 
Eastern right-of-way line of said proposed Paramount Parkway; thence along the 
said Eastern right-of-way line of Paramount Parkway the following calls: 
Northwesterly 268.57 feet along a non-tangential curve to the left, central 
angle 15 degrees 27 minutes 55 seconds, radius 995.00 feet to a point of 
tangency; thence North 85 degrees 47 minutes 19 seconds West 114.70 feet to a 
point of curvature; thence Northwesterly 153.38 feet along a tangential curve 
to the right, central angle 33 degrees 32 minutes 30 seconds, radius 262.00 
feet to a point of tangency; thence North 52 degrees 14 minutes 49 seconds West 
11.29 feet to a point of curvature; thence leaving said proposed Paramount 
Parkway Eastern right-of-way line, Northwesterly 49.22 feet along a tangential 
curve to the right, central angle 93 degrees 59 minutes 54 seconds, radius 
30.00 feet to a point of tangency in the said Eastern right-of-way line of Road 
"A"; thence along said Eastern right-of-way line of Road "A", North 41 degrees 
45 minutes 05 seconds East 849.98 feet to the Point of Beginning.

Said parcel contains 8.50 acres and is the same as shown in a Preliminary Site 
Plans entitled "PARAMOUNT CENTER - LOT 8" prepared by DSAtlantic Corporation 
and dated May 20, 1998 with a last revision date of August 15, 1998.

The boundary description prepared from the Site Plan embodies the Surveyor's 
opinion of the location of the boundary lines of the tract and is not to be 
construed as a certification to quality of title to the property.