<PAGE>

                                                                   EXHIBIT 10.15

                             AGREEMENT OF SUBLEASE
                             ---------------------


          THIS AGREEMENT OF SUBLEASE, made as of the 20th day of April, 1999,
between BURRELL COMMUNICATIONS GROUP, INC., a Delaware corporation, having an
office at 432 Park Avenue South, New York, New York ("Sublessor") and MICROCOM
TECHNOLOGIES, INC. a New York corporation, having an office at 16 East 52nd
Street, New York, New York ("Sublessee"),

                             W I T N E S S E T H :

          WHEREAS, Sublessor is the holder of the lessee's interest in, to, and
under a Lease, dated as of March 15, 1996, between 432 Park South Realty Co.,
LLC ("Landlord") and Sublessor, as amended by an Amendment to Lease dated May 5,
1998 (as amended, the "Lease"), covering the entire rentable area of the 16th
and 12th Floors (collectively, the "Leased Premises") in the building commonly
known and referred to as 432 Park Avenue South, New York, New York (the
"Building"); and

          WHEREAS, Sublessor desires to lease to Sublessee and Sublessee desires
to lease from Sublessor, the entire rentable area of the 12th Floor (the
"Demised Premises") as more specifically set forth in the sketch attached hereto
as Exhibit A on the terms and conditions and for the term as hereinafter set
forth;

          NOW, THEREFORE, in consideration of the mutual covenants and
agreements herein contained, the parties for themselves and, as permitted
hereunder, their successors and assigns, covenant and agree as follows:

          1.   Sublessor does hereby lease to Sublessee and Sublessee does
hereby hire and take from Sublessor the Demised Premises for a term (the "Term")
commencing as of the date written approval of this Sublease is received by
Sublessee from Landlord (the "Commencement Date") and ending on April 19, 2004
(the "Expiration Date") unless such term shall sooner terminate as herein
provided.

          2.   A.   Sublessee shall pay to Sublessor base rent for the Demised
Premises ("Base Rent"), in advance in equal monthly installments on the first
day of each and every month during the Term (except that the first monthly
installment coming due hereunder shall be paid at execution hereof), without
prior demand therefor and without set off or reduction whatsoever, at the
following annual rental rates: during the period commencing with the
Commencement Date

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and ending with April 19, 2000, $261,000.00 per year ($21,750.00 each month);
during the period commencing with April 20, 2000, and ending with April 19,
2001, $268,830.00 per year ($22,402.50 each month); during the period commencing
with the April 20, 2001 and ending with April 19, 2002, $276,894.90 per year
($23,074.58 each month); during the period commencing with the April 20, 2002
and ending with April 19, 2003 $285,201.75 per year ($23,766.81 each month); and
during the period commencing with the April 20, 2003 and ending with April 19,
2004, $293,757.80 per year ($24,479.82 each month);

          B.   Notwithstanding anything contained in paragraph A of this Article
2 to the contrary, Sublessor agrees that Sublessee shall be entitled to an
abatement of the Base Rent for a period of one full month immediately following
the Commencement Date.

          C.   If the Commencement Date shall not occur on the first day of a
calendar month, the monthly rent installment for such calendar month (or the
month for which Base Rent is first payable pursuant to the terms of paragraph B
of this Article 2) shall be prorated on a per diem basis and Sublessor shall
credit the excess amount paid on the execution of this Lease for the payment of
Base Rent for the next succeeding calendar month.

          D.   If the Base Rent or any additional rent shall be or become
uncollectible, reduced or required to be refunded by virtue of any law,
governmental order or regulation, or direction of any public officer or body
pursuant to law, Sublessee shall enter into such agreement or agreements and
take such other action (without additional expense to Sublessee) as Sublessor
may reasonably request, as may be legally permissible, to permit Sublessor to
collect the maximum annual rent and additional rent which may from time to time
during the continuance of such rent restriction be legally permissible, but not
in excess of the amounts of Base Rent or additional rent payable under this
Sublease. Upon the termination of such rent restriction prior to the termination
of the Term of this Sublease, (a) the annual rent and additional rent, after
such termination, shall become payable under this Sublease in the amount of the
Base Rent and additional rent set forth in this Sublease for the period
following such termination, and (b) Sublessee shall pay to Sublessor, to the
maximum extent legally permissible, an amount equal to (i) the additional annual
rent and additional rent which would have been paid pursuant to this Sublease,
but for such rent restriction, less (ii) the annual rent and additional rent
paid by Sublessee to Sublessor during the period that such rent restriction was
in effect.

          3.   Sublessee shall also pay to Sublessor, Sublessee's proportionate
share of, as and when the same shall become due under the Lease, additional
rents,

                                       2
<PAGE>

escalations and other charges and costs required to be paid by Sublessor to
Landlord under the Lease for the Leased Premises (hereinafter referred to
collectively as "additional rent"), which amounts shall be based on statements,
bills or invoices of Landlord which will be provided by Sublessor to Sublessee
from time to time upon request, except that for the purposes of this
subparagraph (i) Sublessee's pro rata share of additional rent shall be
calculated on the basis that the Demised Premises constitute 6.25% of the
Building, and (ii) the Base Tax Year (as such term is defined in the Standard
Escalation Clause Rider attached to the Lease) shall be deemed to be July 1,
1999 to June 30, 2000, and Sublessee's pro rata share of increases over the Base
Tax Year shall be 6.25% with respect to the Demised Premises). Notwithstanding
the foregoing, Sublessor shall pay to Sublessee 100% of the additional rent due
to Landlord from Sublessor with respect to consumption of electricity shown on
the submeter which has been or is to be installed by Sublessor at Sublessor's
sole cost and expense and which submeter Sublessor represents measures the
consumption of electricity in the Demised Premises only. The remedies afforded
Sublessor for the non-payment of such additional rent by Sublessee shall be the
same as for non-payment of Base Rent. Sublessee shall also pay Sublessor within
fifteen days after demand therefor, all charges, costs and expenses incurred by
Sublessee with respect to services or repairs directly provided by Landlord or
Sublessor to the Demised Premises including, but not limited to, additional
cleaning charges, additional heating or overtime charges for heating,
electricity or guard service, supplies and materials, freight elevator services,
electricity, oil, gas and water consumption.

     4.   A.   Sublessee agrees to secure and keep in force from and after the
date Sublessor shall deliver possession of the Demised Premises to Sublessee
and throughout the term, at Sublessee's own cost and expense (A) Comprehensive
General Liability Insurance, in the broadest form available in the State of New
York, with a minimum limit of liability in amounts set by Sublessor and in no
event less than the amount of $1,000,000 combined single limit for injury or
death to any one person and $3,000,000 combined single limit for injury or death
arising out of any one occurrence; and which insurance shall contain (1)
personal injury liability including libel and slander, false arrest, defamation
of character, wrongful eviction, invasion of privacy and deletion of the
employee/agent/contractor exclusion, (2) fire damage legal liability on real
property in the minimum amount of $1,000,000, (3) Worker's Compensation
Insurance, as required by law; and (4) such other insurance in such amounts as
Sublessor, Landlord, any superior mortgagee or any superior landlord may
reasonably require from time to time. Sublessor, Landlord, or any superior
mortgagee and any superior landlord shall be named as additional insured under
such policies.

          B.   All policies of insurance procured by Sublessee shall be issued
in forms and by insurance carriers reasonably acceptable to Sublessor.

                                       3
<PAGE>

Before Sublessor shall deliver possession of the Demised Premises to Sublessee,
Sublessee shall provide Sublessor with certificates of insurance evidencing the
insurance coverages set forth in this Article. Such certificates shall provide
that, in the event of cancellation or material change, thirty days prior written
notice shall be given to Sublessor and all such other named insureds. Each
policy of insurance shall contain a waiver of the insurance carrier's right of
subrogation against the Sublessor, Landlord, superior mortgagee and superior
landlord as respects loss, damage or destruction by fire or other insured
casualty occurring while this Sublease is in effect.

              C.   Sublessor's insurance, if any, shall contain waivers of
subrogation with respect to Sublessee.

         5.   Sublessee acknowledges it has read and examined the Lease, and is
fully familiar with the terms, covenants and conditions on the Sublessor's part
to be performed thereunder, and all of the applicable terms, covenants and
conditions of the Lease are included herein as if set forth in such Lease,
except that the following articles of the Lease shall not be part of this
Sublease: the entire preface to the Lease and Articles 1, 48, 49, 58, 60, 62,
75, 108, 114, 117, 122, 123, 125, 127, 128, 129 and the entire Work Letter.
Unless the context requires otherwise or specific provisions to the contrary are
set forth in full in this Sublease, (i) all rights and remedies reserved to the
"Owner" under the Lease shall be deemed reserved to Sublessor hereunder as if
set for in full and (ii) all duties and obligations imposed upon the "Tenant"
under the Lease (to the extent relating to the Demised Premises) shall be deemed
impose upon Sublessee hereunder; provided, however, that any notice, grace or
                                 --------- -------
cure periods available to Sublessee shall be deemed shorted by two business
days. To the extent that any provision of the Lease requires the "Tenant"
thereunder to obtain the consent of the "Owner", such provision shall be deemed
to require the consent of both the Landlord and the Sublessor.

         6.   Sublessee shall not assign, sublet, mortgage or allow others to
use the Demised Premises without Sublessor's prior written consent, which
consent shall not be unreasonably withheld or delayed, and shall not use or
permit or suffer the use of the Demised Premises for any other business or
purpose. Sublessee agrees to conduct Sublessee's business in the Demised
Premises under Sublessee's trade name first above appearing, which Sublessee
represents that it has the right so to use.

         7.   Sublessee does hereby assume and agree to be bound by and perform
all the aforesaid terms, covenants and conditions on the Sublessor's part (as
tenant under the Lease) to be performed under the Lease with respect to the
Demised Premises except as otherwise herein specified, and Sublessee agrees to

                                       4
<PAGE>

indemnify, defend (by counsel reasonable acceptable to Sublessor) and hold
Sublessor harmless against any claim or liability asserted against Sublessor by
reason of Sublessee's failure to perform such obligations. Sublessee agrees that
this Sublease is separate from and subordinate in all respects to the Lease (and
amendments thereto) and to any agreement to which the Lease is subject.
In the event Sublessee shall default in the full performance of any of the
terms, covenants and conditions on its part to be performed under this Sublease,
then Sublessor shall have the same rights and remedies with respect to such
default as are given to Landlord with respect to defaults by Sublessor herein
and as tenant under the Lease, all with the same force and effect as though the
provisions of the Lease with respect to defaults, and the rights and remedies of
Landlord in the event thereof, were set forth at length herein. Sublessee
further agrees that Sublessor shall have no liability of any nature whatsoever
to Sublessee as a consequence of Landlord's default under the Lease, including,
but not limited to, Landlord's breach of a covenant of quiet enjoyment. Any
conflicts between the terms and conditions of this Sublease and the Lease
shall be resolved in favor of this Sublease.

          8.   If Sublessee shall default (beyond any applicable grace period in
the Lease) in the performance of any of Sublessee's obligations hereunder,
Sublessor, without thereby waiving such default, may, at Sublessor's option,
after 20 days notice to Sublessee, perform the same for the account of
Sublessee. If Sublessor makes any expenditures or incurs any obligations for the
payment of money, including reasonable attorneys' fees, in connection with
curing Sublessee's defaults or in instituting, prosecuting or defending any
action or proceeding, by reason of any default of Sublessee hereunder, such sums
paid or obligations incurred, with interest thereon at 2% per month, shall be
paid by Sublessee to Sublessor as additional rent within ten days of rendition
of any bill or statement to Sublessee therefor and Sublessor shall have the same
rights with respect thereto and Sublessee shall have the same obligations
therefor as if same constituted Base Rent hereunder.

          9.   Sublessee shall be entitled to receive all services to be
rendered to the Sublessor under the Lease in so far as such services pertain to
the Demised Premises and Sublessee shall be responsible for all charges relating
thereto as provided in the Lease. Sublessor shall have no liability of any
nature whatsoever to Sublessee for Landlord's failure to perform or render such
services and Sublessee shall look solely to Landlord for all such services and
shall not, under any circumstances, seek nor require Sublessor to perform any of
such services, nor shall Sublessee make any claim upon Sublessor for any damages
which may arise by reason of Landlord's default under the Lease, or Landlord's
negligence, whether by omission or commission. If Landlord shall default in the
performance or observance of any of its agreements or obligations under the
Lease, Sublessor shall have no liability therefor to Sublessee and there shall
not be in any event construed

                                       5
<PAGE>

to exist any corresponding obligation by Sublessor to Sublessee for any such
services or other obligations under this Sublease.  No such default of Landlord
shall excuse Sublessee from the performance of any of its obligations to be
performed under this Sublease or entitle Sublessee to terminate this Sublease or
to reduce or abate or offset any of the rents provided for in this Sublease.  In
furtherance of the foregoing, Sublessee does, to the extent permitted by law,
and except for the willful acts of Sublessor, hereby waive any cause of action
and any right to bring any action against Sublessor by reason of any act or
omission of Landlord.  The foregoing notwithstanding, Sublessor shall use its
best efforts and will cooperate in all respects with Sublessee, the costs of
which to be reimbursed by Sublessee as additional rent, to obtain services to be
provided by Landlord under the Lease and take all actions necessary with respect
thereto.

          10.  A.   Sublessee agrees that if by reason of default on the part
of Sublessor or Landlord under any ground, superior or underlying lease or any
mortgage on the Building, land and/or improvements or on any such ground,
superior or underlying lease, a ground, superior or underlying lessor or a
mortgagee shall enter into and become possessed of the real property of which
the Demised Premises form a part, or any part or parts of such real property
either through possession or foreclosure action or proceedings, or through the
issuance and delivery of a deed or a new lease of the premises covered by the
ground, superior or underlying lease, then, if this Sublease is in full force
and effect at such time, Sublessee shall attorn to such lessor or such
mortgagee, as its landlord; in such event, such lessor or mortgagee shall not be
liable to Sublessee for any defaults theretofore committed by Sublessor and no
such default shall give rise to any rights of offset or deduction against the
Basic Rent and additional rent payable under this sublease.

               B.   The provisions for attornment hereinbefore set forth shall
not require the execution of any further instrument. However, if any such lessor
or mortgagee to which Sublessee agrees to attorn, as aforesaid, requests a
further instrument expressing such attornment, Sublessee agrees to execute the
same promptly.

          11.  Landlord's consent to this Sublease is a condition precedent to
the effectiveness hereof.  If Landlord's consent or waiver thereof is not
received within thirty days after the date hereof, this Sublease will be void.
In such event, neither party shall have any rights against, or obligations to
the other, except Sublessor shall return all monies deposited hereunder.

          12.  A.   Sublessee covenants, warrants and represents to Sublessor
that, other than Signature Partners, Inc., there was no broker, finder or
similar person entitled to a commission, fee or other compensation, instrumental
in

                                       6
<PAGE>

consummating this Sublease, that no conversations or prior negotiations were had
by Sublessee or anyone acting on behalf of Sublessee with any broker, finder or
similar person concerning the renting of the Demised Premises. Sublessee shall
indemnify and hold Sublessor harmless against and from all costs, expenses,
damages and liabilities, including reasonable attorney's fees and court costs,
arising from any claims for brokerage commissions, finder's fees or other
compensation resulting from or arising out of any conversations, negotiations or
actions had by Sublessee or anyone acting on behalf of Sublessee with any
broker, finder or similar person. Sublessee shall defend against any such claim
by attorneys reasonably satisfactory to Sublessor and shall not enter into any
settlement agreement with respect thereto without either (i) depositing the
amount of such claim together with all costs of Sublessor associated with
defense of such claim, in trust, with Sublessor for payment of such settlement
or (ii) first receiving written authorization therefor, specific in scope and
authority, from Sublessor. Sublessor agrees to pay the broker's commission(s) by
separate agreements.

               B.   Sublessor covenants, warrants and represents to Sublessee
that, other than Signature Partners, Inc., there was no broker, finder or
similar person entitled to a commission, fee or other compensation, instrumental
in consummating this Sublease, that no conversations or prior negotiations were
had by Sublessor or anyone acting on behalf of Sublessor with any broker, finder
or similar person concerning the renting of the Demised Premises. Sublessor
shall indemnify and hold Sublessee harmless against and from all costs,
expenses, damages and liabilities, including reasonable attorney's fees and
court costs, arising from any claims for brokerage commissions, finder's fees
or other compensation resulting from or arising out of any conversations,
negotiations or actions had by Sublessor or anyone acting on behalf of Sublessor
with any broker, finder or similar person. Sublessor shall defend against any
such claim by attorneys reasonably satisfactory to Sublessee and shall not enter
into any settlement agreement with respect thereto without either (i) depositing
the amount of such claim together with all costs of Sublessee associated with
defense of such claim, in trust, with Sublessee for payment of such settlement
or (ii) first receiving written authorization therefor, specific in scope and
authority, from Sublessee.

          13.  Sublessee acknowledges and agrees that Sublessor shall have no
obligations, liability or responsibility with respect to the condition of the
Demised Premises or the installations therein, at the commencement of the Term
or at any time thereafter, it being agreed that Sublessee shall accept the
Demised Premises in "as is" condition. Sublessee acknowledges that neither
Sublessor, nor Sublessor's agents, have made any representations or promises in
regard to the Demised Premises. The taking of possession of the Demised Premises
by Sublessee shall be conclusive evidence as against Sublessee that Sublessee
accepts the same "as-is" and that the Demised Premises were in good and
satisfactory

                                       7
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condition at the time such possession was taken.

         14. A.    Notwithstanding anything contained in any provision of this
Sublease to the contrary, Sublessee agrees, with respect to the Demised
Premises, to comply with and remedy any default claimed by Landlord under the
Lease and caused by Sublessee, within the period allowed to Sublessor as tenant
under the Lease minus three days, even if such time period is shorter than the
period otherwise allowed in the Lease due to the fact that notice of default
from Sublessor to Sublessee is given after the corresponding notice of default
from Landlord to Sublessor as tenant under the Lease. Sublessor agrees to
forward to Sublessee, by hand promptly upon receipt thereof by Sublessor, a copy
of each notice of default received by Sublessor in its capacity as tenant under
the Lease. Sublessee agrees to forward to Sublessor, upon receipt thereof,
copies of any notices received by Sublessee with respect to the Demised Premises
from Landlord or from any governmental authorities.

             B.    Sublessee shall deposit with Sublessor $65,250.00 as security
deposit (the "Security Deposit" or "security") at execution of this Sublease to
be held as security for the faithful performance and observance by Sublessee of
the terms, provisions and conditions of this Sublease; it is agreed that in the
event Sublessee defaults in respect of any of the terms, provisions and
conditions of this Sublease, including, but not limited to, the payment of Base
Rent and additional rent, Sublessor may use, apply or retain the whole or any
part of the security so deposited to the extent required for the payment of any
Base Rent and additional rent or any other sum as to which Sublessee is in
default or for any sum which Sublessor may expend or may be required to expend
by reason of Sublessee's default in respect of any of the terms, covenants and
conditions of this Sublease, including but not limited to, any damages or
deficiency in the re-letting of the Demised Premises, whether such damages or
deficiency accrued before or after summary proceedings or other re-entry by
Sublessor. In the event that Sublessee shall fully and faithfully comply with
all of the terms, provisions, covenants and conditions of this Sublease, the
security shall be returned to Sublessee after the date fixed as the end of the
Sublease and after delivery of entire possession of the Demised Premises to
Sublessor. In the event of a sale of the leased premises, of which the Demised
Premises form a part, Sublessor shall have the right to transfer the security to
the vendee or lessee and Sublessor shall thereupon be released by Sublessee from
all liability for the return of such security, and Sublessee agrees to look to
the new Sublessor solely for the return of said security; and it is agreed that
the provisions hereof shall apply to every transfer or assignment made of the
security to a new Sublessor. Sublessee further covenants that it will not assign
or encumber or attempt to assign or encumber the monies deposited herein as
security and that neither Sublessor nor its successors or assigns shall be bound
by any such assignment, encumbrance, attempted assignment or attempted
encumbrance.

                                       8
<PAGE>

Sublessee shall have the right, in lieu therefore or at any time thereafter in
substitution for such funds, to deposit and maintain with Sublessor as the
Security Deposit referred to in the Lease, an irrevocable commercial letter of
credit in the aggregate amount of $65,250.00 in form and substance, and issued
by a member bank of the New York Clearinghouse Association, acceptable to
Sublessor, payable upon the presentation by Sublessor to such bank of a sight-
draft, without presentation of any other documents, statements or
authorizations, which letter of credit shall provide (i) for the continuance of
such credit for the period of at least one year from the date of execution
hereof, (ii) for the automatic extension of such letter of credit for additional
periods of one year from the initial and each future expiration date thereof
(the last such extension to provide for the continuance of such letter of credit
for at least 30 days beyond the expiration date of the Term) unless such bank
gives Sublessor notice of its intention not to renew such letter of credit, not
less than 30 days prior to the initial or any future expiration date of such
letter of credit and (iii) that in the event such notice is given by such bank,
Sublessor shall have the right to draw on such bank at sight for the balance
remaining in such letter of credit and hold and apply the proceeds thereof in
accordance with the provisions of this Sublease. Each letter of credit to be
deposited and maintained with Sublessor (or the proceeds thereof) shall be held
by Sublessor as security for the faithful performance and observance by
Sublessee of the terms, provisions and conditions of this Sublease and in the
event that (x) any default occurs as provided in this Sublease, or (y) Sublessor
transfers its right, title and interest under this Sublease to a third party and
the bank issuing such letter of credit does not consent to the transfer of such
letter of credit to such third party, or (z) notice is given by the bank issuing
such letter of credit that it does not intend to renew the same, as above
provided, then, in any such event, Sublessor may draw on such letter of credit,
and the proceeds of such letter of credit shall then be held and applied as
security (and be replenished, if necessary) as herein provided. Sublessor shall
deposit the security (if cash) in a segregated interest bearing account and the
interest shall be paid to Sublessee on an annual basis, subject to the rights of
Sublessor in the security as herein provided.

          15.  All notices required by, or provided in connection with, this
Sublease shall be sent by certified mail, return receipt requested, and
personally delivered to the Sublessor at its address first appearing herein and
to Sublessee at the Demised Premises or such other address as either party may
designate by notice as provided herein and notice shall be deemed effected upon
such delivery and such posting with the U.S. Postal Service and if to Sublessor,
after a copy has been sent to Winston & Strawn, 200 Park Avenue, New York, New
York 10166, attn: John C. Phelan and if to Sublessee, after a copy has been sent
to Gould & Wilkie LLP, One Chase Manhattan Plaza, New York, New York 10005,
attn: Michael R. Manley.

                                       9

<PAGE>

     16.  In the event Sublessee, or anyone claiming status through or on
behalf of Sublessee, remains in possession of the Demised Premises after the
expiration or earlier termination of this Sublease without the execution of a
new sublease or a direct lease with Landlord, (i) Sublessor shall be entitled
to all of the rights and remedies which are available to a landlord against a
tenant holding over after the expiration of a term and to such other rights and
remedies as may be provided for in this Sublease at law or in equity, and (ii)
Sublessee, at the option of Sublessor, shall be deemed to be occupying the
Demised Premises as a tenant from month to month, at a monthly rental equal to
two times the Base Rent, plus the additional rentals payable hereunder, subject
to all of the other terms of this Sublease insofar as the same are applicable to
a month-to-month tenancy.

     17.  The provisions of the Lease notwithstanding, and in addition thereto,
with respect to any provision of this Sublease which provides, in effect, that
Sublessor shall not unreasonably withhold or unreasonably delay any consent or
any approval, Sublessee shall, in no event, be entitled to make, nor shall
Sublessee claim any money damages by way of setoff, counterclaim or defense,
based upon any claim or assertion by Sublessee that Sublessor has unreasonably
withheld or unreasonably delayed any consent or approval; but Sublessee's sole
remedy shall be an action or proceeding to enforce any such provision, or for
specific performance, injunction or declaratory judgment. In any event where
Landlord grants it consent to any request of Sublessee, Sublessor's consent
shall be deemed granted so long as Sublessee holds Sublessor harmless from any
costs associated with or resulting therefrom.

     18.  The provisions of the Lease notwithstanding, and in addition thereto,
Sublessee agrees that Sublessee shall make no claim against Sublessor for any
injury or damage to Sublessee or to any other person(s) or for any damage to, or
loss (by theft or otherwise) of any property of Sublessee or of any other
person. Sublessee further agrees to indemnify and save harmless Sublessor
against and from any and all claims by or on behalf of any person(s), firm(s) or
corporation(s) arising from the conduct or management of or from any work or
thing whatsoever done (other than by Sublessor or its agents or employees) in
and on the Demised Premises during the term of this Sublease, and to indemnify
and save harmless Sublessor against and from any and all claims arising from any
condition of the Demised Premises due to or arising from any act or negligence
of Sublessee or any of its agents, contractors, servants, employees, licensees
or invitees, and from and against all costs, expenses and liabilities incurred
in or in connection with any such claim or claims or action or proceeding
brought thereon; and, in case any action or proceeding be brought against
Sublessor by reason of any claim, Sublessee upon notice from Sublessor agrees to
resist or defend such action or proceeding and to employ counsel therefor
reasonably satisfactory to Sublessor; it being understood that counsel for
Sublessee's insurers shall be deemed to be satisfactory

                                      10
<PAGE>

to Sublessor.

     19.  Whenever Sublessee requests the consent or approval of Sublessor,
Sublessee shall pay to Sublessor, as additional rent within 10 days after
Sublessor has submitted an invoice or bill to Sublessee, Sublessor's costs of
review and/or approval including, but not limited to, costs of architects,
Landlord, attorneys, engineers or others, and shall pay all costs assessed by
Landlord against Sublessor resulting therefrom. This provision shall not apply
to initial alterations of the Demised Premises or any alterations to which
Landlord shall have consented so long as Sublessee shall remove the same if
Landlord so requires.

     20.  A.   Sublessee shall have the right, at both Sublessee and Sublessor's
option, to renew this Sublease, for the Demised Premises for a renewal term
("Renewal Term") of four years. The Renewal Term shall commence on the day after
the Expiration Date ("Renewal Term Commencement Date") and shall terminate on
the fourth anniversary of the Expiration Date. Sublessee shall exercise the
option described herein by giving Sublessor written notice of such election to
renew (the "Election Notice"), not later than six months prior to the Expiration
Date. Upon receipt of such Election Notice by Sublessor, Sublessor shall have
the option to renew this Sublease for the Renewal Term by giving Sublessee
written notice of its acceptance of Sublessee's Election Notice (the "Acceptance
Notice"). Upon the giving of the Election Notice and the Acceptance Notice, this
Sublease shall thereupon be deemed renewed for the Renewal Term with the same
force and effect as if the Renewal Term had originally been included in the term
of this Sublease. The right of Sublessee to renew this Sublease shall be
conditioned upon Sublessee not being in default beyond any applicable grace
periods under the Sublease and upon the Sublease being in full force and effect
at the time of the exercise of such option and as of the Renewal Term
Commencement Date.

          B.   All of the terms, covenants and conditions of this Sublease shall
continue in full force and effect during the Renewal Term, except that (i) the
Base Rent for the Renewal Term shall be in an amount equal to three percent
increases each year over the Renewal Term, and (ii) Sublessee shall have no
further right to renew the Term of this Sublease. Any termination, cancellation
or surrender of the entire interest of Sublessee under this Sublease at any time
during the Term hereof shall terminate any right of renewal of Sublessee
hereunder. Upon the determination of the Base Rent in accordance with this
Article 20 for the Renewal Term, Sublessor and Sublessee, upon the demand of
either of them, shall execute and deliver an instrument setting forth the Base
Rent for the Renewal Term.

     21.  Sublessee, for itself and on behalf of any and all persons claiming
through or under Sublessee, including creditors of all kinds, does hereby

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<PAGE>

waive and surrender all right and privilege it or they or any of them might have
under or by reason of any present or future law, to redeem the Demised Premises
or to have a continuance of this Sublease for the term hereby demised after
being dispossessed or ejected therefrom by process of law or under the terms of
this Sublease or after the termination of the Term of this Sublease as herein
provided.

          22.  Any provision of the Lease to the contrary notwithstanding,
Sublessee covenants and agrees that Sublessee shall not assign, mortgage, or
pledge this Sublease, or sublease or allow others to occupy all or any part of
the Demised Premises, without the prior written consent of Landlord and
Sublessor in each instance first obtained. In the event Landlord grants its
consent, Sublessor's shall be deemed granted.

          23.  Sublessee agrees to pay all commercial occupancy taxes due in
connection with Sublessee's occupancy of the Demised Premises.

          24.  Unless otherwise stated, the terms, covenants and conditions
contained in this Sublease shall bind and inure to the benefit of the parties
hereto and their respective heirs, distributees, executors, administrators and,
only as permitted herein, successors and assigns.

          25.  Sublessor has made no representations, agreements or promises
with respect to the Building or the Demised Premises other than those expressly
set forth in this Sublease and no rights are to be deemed acquired by Sublessee,
by implication or otherwise, except those expressly granted herein. This
Sublease and the appropriate provisions of the Lease contain the entire
agreement between Sublessor and Sublessee with respect to the Demised Premises.
Any executory agreement hereafter made between Sublessor and Sublessee shall be
ineffective to change, modify, waive, release, discharge, terminate or effect an
abandonment or surrender of this Sublease, in whole or in part, unless such
agreement is in writing and signed by the party against whom enforcement thereof
is sought.

          26.  If Sublessee is a corporation, the persons executing this
Sublease on behalf of Sublessee hereby covenant, represent and warrant that
Sublessee is a duly incorporated or duly qualified (if foreign) corporation and
is authorized to do business in the State of New York (a copy of evidence
thereof to be supplied to Sublessor upon request); and that the person or
persons executing this Sublease on behalf of Sublessee is an officer or are
officers of such Sublessee, and that he or they as such officers are duly
authorized to execute, acknowledge and deliver this Sublease to Sublessor (a
copy of a resolution or secretary's certificate to that effect to be supplied to
Sublessor upon request).

          27.  Under no circumstances shall Sublessee be required to pay any

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<PAGE>

charges required under the Lease and shall only pay such charges specifically
reserved in this Sublease. If the Lease is ever amended, Sublessor shall provide
Sublessee with notice of such amendment and promptly deliver a copy of same to
Sublessee. In addition, Sublessor shall provide Sublessee with copies of any
notices Sublessor receives from or delivers to Landlord. Throughout the term of
this Sublease, Sublessor covenants that it will actively pursue its rights
against Landlord under the Lease (i.e., repair obligations, heat, air
conditioning, etc.). Sublessor represents to Sublessee that so long as Sublessee
shall fully comply with and perform all of Sublessee's obligations hereunder,
Sublessee shall not be in violation of any of the terms of the Lease.

          28. Sublessor represents to Sublessee that, to the best of Sublessor's
knowledge, it is not in default under the terms of the Lease. In addition,
Sublessor represents to Sublessee that it has not received any default notices
or petitions from Landlord.

          29. Sublessor acknowledges and agrees that this Sublease is contingent
upon the Sublessee's receipt of valid and binding Non-Disturbance Agreement from
the Landlord with respect to Sublessee's subtenancy in substantially the same
form as set forth on Exhibit B attached hereto.

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<PAGE>

          IN WITNESS WHEREOF, Sublessor and Sublessee have executed and
delivered this Agreement of Sublease as of the date first hereinabove written.


                                             BURRELL COMMUNICATIONS GROUP, INC.,
                                             as Sublessor


                                             By: /s/ John Stanek
                                                --------------------------
                                             Name:  John Stanek
                                             Title: EVP CFO


                                             MICROCOM TECHNOLOGIES, INC.,
                                             as Sublessee


                                             By: /s/ Thomas Egan
                                                --------------------------
                                             Name:  Thomas Egan
                                             Title: President/COO

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