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                                                              Exhibit 10.18(b)

                               SUBLEASE AGREEMENT

      AGREEMENT made this 30th day of June, 1998, by and between ICO, LLC, a
Massachusetts limited liability company, with offices c/o Arthur Ivey at
Heritage on the Common, 300 Boylston Street, Unit 507, Boston, MA 02116
(hereinafter called "Sublessor"), and Keith Rodney Company, Inc. a Massachusetts
corporation with offices at 545 Boylston Street, Boston, MA 02216 (hereinafter
called "Sublessee").

                                   WITNESSETH:

      WHEREAS, by Agreement of Lease dated as of Oct 9, 1996, by and between Net
Realty Holding Trust, as landlord (hereinafter called the "Landlord of the
Underlying Lease") and Sublessor as tenant, (hereinafter called the "Underlying
Lease"), a copy of which is annexed hereto, made a part hereof and marked
Exhibit "A", the said landlord did lease to the said tenant certain premises
located on the 8th floor of the building known as and numbered 545 Boylston
Street in the City of Boston, County of Suffolk, and Commonwealth of
Massachusetts, as more particularly described in the Underlying Lease (referred
to in the underlying Lease as the "Premises"), and

      WHEREAS, Sublessor desires to sublease the Demised Premises (hereinafter
called the "Subleased Premises") to the Sublessee and the Sublessee is willing
to sublet the Subleased Premises from Sublessor on the conditions hereinafter
set forth,

      NOW, THEREFORE, in consideration of the mutual covenants and agreements
hereinafter set forth, it is hereby agreed by and between the parties hereto as
follows:

                                    ARTICLE I

                               Subleased Premises

      Sublessor hereby subleases unto Sublessee, and Sublessee hereby takes and
hires from Sublessor, subject to the terms, conditions and provisions hereof,
the Subleased Premises which constitute all of the Premises described in said
Underlying Lease, together with any rights appurtenant to said Subleased
Premises granted to Sublessor in the Underlying Lease. Sublessee shall have all
the rights, privileges and benefits of the "Tenant" of such Underlying Lease
pertaining to the Subleased Premises except as herein specifically limited or
denied, and the same are hereby granted and conveyed to Sublessee from Sublessor
for the full term hereof.

                                   ARTICLE II

                                      Term

      The term of this Sublease shall be for a period of three (3) years and
eight (8) months commencing on July 1, 1998, and terminating on February 28,
2002 (the "Term").

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                                   ARTICLE III

                           Rent, Taxes and Assessments

      Sublessee covenants and agrees to pay the following to Sublessor, at such
place or places as Sublessor may by notice in writing to Sublessee from time to
time direct, at the following rates and times:

      (a) Annual Rent. Annual rent at the rate of one hundred twenty-six
thousand, one hundred thirty-nine ($126,139.00) Dollars payable each month in
equal installments of ten thousand, five hundred eleven and 58/100 ($10,511.58)
Dollars in advance, on the first day of each and every calendar month,
commencing on July 1, 1998 and prorated for the fraction of any month, without
offset, deduction, notice or demand.

      (b) Additional Rent. Sublessee shall pay to Sublessor, as additional rent,
all real estate taxes which Sublessor may be obligated to pay pursuant to the
terms of Article 7 of the Underlying Lease, any increases in Operating Expenses
which Sublessor may be obligated to pay pursuant to the terms of Article 8 of
the Underlying Lease, and any other charges which Sublessor may be obligated to
pay pursuant to the Underlying Lease during the term of this Sublease. The
amounts due hereunder pursuant to the aforesaid provisions of the Underlying
Lease shall be payable to Sublessor no less than ten (10) days prior to the date
that Sublessor may be obligated to pay same pursuant to the terms of said
Underlying Lease.

      (c) All rental and additional rental shall be paid to Sublessor at the
address set forth above, or such other address as Sublessor may designate in
writing.

                                   ARTICLE IV

                                       Use

      Sublessee shall have the right to use the Subleased Premises for the use
permitted by Article 9 of the Underlying Lease and for no other purpose.

                                    ARTICLE V

                            Condition of the Premises

      Sublessee accepts the Subleased Premises in "as-is" condition.

      Sublessor shall deliver possession of the Subleased Premises to Sublessee
on July 1, 1998, subject to delays beyond Sublessor's reasonable control, but in
no event prior to the execution of this Sublease and the delivery of the rental
required hereunder.


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                                   ARTICLE VI

                            Assignment and Subletting

      Sublessee shall not have the right to assign Sublessee's interest in the
Sublease or sublease the Subleased Premises in whole or in part during the term
hereof, by operation of law or otherwise.

                                   ARTICLE VII

                            Subordination of Sublease

      It is understood that the Sublessor is not the fee owner of the Subleased
Premises, but has acquired its interest therein solely through the Underlying
Lease. This Sublease is subject to the provisions of the Underlying Lease and
subordinate thereto. In the event that the Underlying Lease shall be cancelled
or terminated, the term of this Sublease shall automatically terminate as of the
date of such cancellation or termination of the Underlying Lease and the
Sublessor shall not be liable in any way or to any extent to the Sublessee for
such termination or cancellation or for any damages or losses incurred or
claimed to be incurred by Sublessee as a result thereof.

                                  ARTICLE VIII

                        Incorporation of Underlying Lease

      (a) Except as otherwise herein provided, this Sublease is subject to all
of the terms, covenants and conditions of the Underlying Lease and said terms,
covenants and conditions are incorporated herein by reference and made a part of
this Sublease as if fully set forth herein except as otherwise stated in Article
VIII, Paragraph (b) below. The words "Landlord" and "Tenant", as utilized in the
provisions of the Underlying Lease incorporated herein shall be deemed to refer
for the purposes of this Sublease, to Sublessor and Sublessee respectively and
the words "this lease" shall mean this Sublease. With respect to the Subleased
Premises, and only as between Sublessor and Sublessee, Sublessor shall have the
rights and obligations of the Landlord of the Underlying Lease as set forth in
the Underlying Lease, and Sublessee shall have the rights and obligations of the
tenant of the Underlying Lease as set forth in the Underlying Lease, except
where such rights and obligations are deleted, modified or altered herein.

      (b) If any of the provisions of this Sublease are at variance or in
conflict with the provisions of the Underlying Lease due to a deletion,
modification or alteration of such provisions herein, the provisions of this
Sublease shall govern and control.

      (c) Sublessee covenants that it will not commit, or suffer to be
committed, any act or act of omission in violation of the terms and provisions
of the Underlying Lease so as to render the Sublessor in default in any of the
terms, covenants and conditions of the Underlying Lease.

      (d) In the event of any default by the Landlord of the Underlying Lease
under the terms thereof, Sublessee shall give the Sublessor and the Landlord of
the Underlying Lease written notice thereof. Sublessor shall not be responsible
or liable for the failure by the Landlord of the Underlying Lease to furnish to
Sublessee any service or facility required under the Underlying Lease to be


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furnished or provided and Sublessor will use its best efforts to compel the
Landlord of the Underlying Lease to cure any such default pursuant to the terms
of the Underlying Lease.

                                   ARTICLE IX

                                     Default

      (a) In the event that Sublessee shall default in the payment of annual
rent herein reserved and/or any additional rental when due, Sublessor shall
notify Sublessee in writing of such default, and Sublessee shall have five (5)
days from the date of such notice to cure such default.

      (b) In the event that Sublessee shall default in the performance of any
obligations hereunder when due, except the payment of annual rent and/or
additional rent herein reserved, Sublessor shall notify Sublessee in writing of
such default, and Sublessee shall have twenty (20) days from the date of such
notice to cure such default.

      (c) Except in the event of a default, as provided in Subparagraphs (a) and
(b) set forth above:

            (i) Whenever a time period is specified in the Underlying Lease
      within which the tenant therein must give notice or make a demand
      following an event, or within which said tenant must respond to any
      notice, request or demand previously given or made by the landlord, or
      comply with any obligation thereunder on such tenant's part, such time
      period is hereby changed (for purposes of this Sublease only) by
      subtracting ten (10) days therefrom; and

            (ii) whenever a time period is specified in the Underlying Lease
      within which the landlord must give notice or make a demand following an
      event or within which the landlord must respond to any notice, request or
      demand previously given or made by the tenant thereunder, or comply with
      any obligation thereunder on landlord's part, such time period is hereby
      changed (for purposes of this Sublease only) by adding ten (10) days
      thereto.

It is the intent of this section to provide Sublessor with time within which to
transmit to the Landlord of the Underlying Lease any notices or demands received
by Sublessor from Sublessee, and to transmit to Sublessee any notices or demands
received by Sublessor from the Landlord of the Underlying Lease.

                                    ARTICLE X

                               General Provisions

      (a) Any insurance required to be carried by Sublessee pursuant to the
provisions of the Underlying Lease as incorporated herein shall name the
Landlord of the Underlying Lease as well as Sublessor, as additional insured
parties and, if requested, any mortgagee of the Underlying Landlord.

      (b) The purpose and intent of this Sublease is that the rental provided
for in Article III hereof shall be absolutely net to the Sublessor except as
expressly provided to the contrary herein. In this connection, Sublessor shall
not have any obligation to construct, maintain, alter or repair the


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Subleased Premises or any facilities or improvements thereon or appurtenant
thereto or be obligated to provide Sublessee with any service or facility, but
shall be obligated only to use its best efforts to compel the Landlord of the
Underlying Lease to perform such duties if said Landlord has covenanted to do so
under the terms of the Underlying Lease.

      (c) Sublessee shall, upon the request of Sublessor, subordinate this
Sublease to the lien of any present or future mortgage upon the Demised Premises
and/or the Subleased Premises irrespective of the time of execution or recording
of any such mortgage.

      (d) Sublessee shall not have any of the tenant's rights specified in the
provisions of Article 3 (Renewal Option), Article 11 (Preparation of the
Premises), Article 41 (Broker) or Article 44 (Lease Contingency) of the
Underlying Lease.

      (e) Any rights by the tenant to terminate the Underlying Lease provided
therein shall be exercised only by Sublessor when, in its sole opinion, those
conditions precedent required for a termination by tenant under the terms and
conditions of the Underlying Lease have occurred.

      (f) Sublessee shall pay for all utilities provided to the Subleased
Premises including without limitation, gas, water, electricity, sewerage and
telephones. Payments for such charges shall be made as provided in the
Underlying Lease.

                                   ARTICLE XI

                                     Notices

      All notices or communications authorized or required hereunder shall be in
writing and shall be given by mailing the same by certified or registered mail,
return receipt requested, postage prepaid, and any such notice or communication
shall be deemed to have been given when received by the party to whom such
notice or communication shall be addressed. If intended for Sublessor, same
shall be mailed c/o Arthur Ivey to Heritage on the Common, 300 Boylston Street,
Unit 507, Boston, MA 02116 and a copy to Posterrnak, Blankstein & Lund, L.L.P.,
100 Charles River Plaza, Boston, MA 02114, Attn: Robert M. Schlein, Esquire, or
at such other address as Sublessor may hereafter designate by notice to
Sublessee: and if intended for Sublessee, the same shall be mailed to Sublessee
at 545 Boylston Street, Boston, MA 02116, or at such other address as Sublessee
may designate by notice to Sublessor.

                                   ARTICLE XII

                               Merger, Disclaimers

      All understandings and agreements heretofore had between the parties
hereto are merged in this Sublease, which alone fully and completely express
this Sublease, Sublessee has not relied upon or been induced by any statements
or representations, other than those expressly set forth in this Sublease, of
any person in respect of the title to or the physical condition of the Subleased
Premises, or any other matter affecting the Subleased Premises or this
transaction which might be pertinent in considering the execution of this
Sublease. Sublessee expressly acknowledges that no such representations not
embodied herein have been made.


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                                  ARTICLE XIII

                          Entire Agreement and Benefits

      This agreement contains the entire understanding between parties. No
waiver, change, modification or discharge of any of the provisions of this
Sublease shall be valid unless effected by an agreement in writing signed by
both parties hereto. The waiver of any of the provisions of this Sublease shall
not be deemed to be a waiver of any subsequent breach or default of the
provisions hereof. This Sublease shall be binding upon and inure to the benefit
of Sublessor and Sublessee and their respective successors and assigns.

                                   ARTICLE XIV

                                  Severability

      The illegality or invalidity of any provision of this Sublease, by reason
of any rule of law or public policy, shall not affect this Sublease or any other
provisions hereof, but this Sublease shall, nevertheless, remain in full force
and effect and shall be construed in all respects as if such invalid provision
were omitted.

                                   ARTICLE XV

                                  Construction

      This Sublease and the performance thereof shall be construed, regulated
and governed by the laws of the Commonwealth of Massachusetts, where it has been
made and entered into. The section headings have been inserted for convenience
only and shall not enter into the interpretation or construction of this
Sublease.

[Signature on following page.]


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      IN WITNESS WHEREOF, the parties have hereunto set their hands and seals as
of the date and year first above written.

                                      (Sublessor)

                                      ICO, LLC


                                      By
                                        --------------------------------------
                                        Arthur J. Ivey, Managing Member
                                        hereunto duly authorized

                                      (Sublessee)

                                      KEITH RODNEY COMPANY, INC.


                                      By /s/ Keith Rodney
                                         -------------------------------------
                                         Keith Rodney, its President
                                         hereunto duly authorized


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