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                                                                 Exhibit 10.(a)


August 19, 1998

Via Facsimile and Airborne Express

Mr. Robert A. Lange
Sr. Vice President
Lindner Funds
7711 Carendolet Avenue, Suite 700
St. Louis MO  63105

Re:  Redemption of Series C Preferred Stock

Dear Mr. Lang:

This Letter Agreement set forth the terms and conditions under which the parties
have agreed for Interleaf to redeem the Series C Preferred Stock.

Reference is made to the Series C Preferred Stock Purchase Agreement between
Lindner Investments and Interleaf, Inc. ("Interleaf" or the "Company") dated
October 14, 1996 (the "Investment Agreement") pursuant to which Interleaf issued
and sold 1,010,348 shares of Series C Preferred Stock, $.10 par value (the
"Series C Shares") to the Lindner Growth Fund (505,174 shares) and the Lindner
Dividend Fund (505,174 shares) (collectively, the "Lindner Funds").

Our agreement is as follows:

1)   Redemption. Interleaf agrees to redeem and purchase, and the Lindner Funds
     agree to sell, the Series C Shares at a price of $3.04 per share, or
     $3,071,458 in the aggregate (the "Purchase Price").

2)   Closing. The Purchase Price shall be paid to the Lindner Funds and the
     Series C Shares shall be transferred to Interleaf within forty-five (45)
     days following the date on which the Company's Board of Directors approves
     the terms of this Agreement, but no later than October 9, 1998. The closing
     of this transaction (the "Closing") may be effected via courier, wire
     transfer or other means of exchange, as agreed.

3)   Release: Upon delivery of the Series C Shares to Interleaf and payment of
     the Purchase Price to the Lindner Funds, each of Interleaf and the Lindner
     Funds agrees (i) that the Investment Agreement shall be terminated and of
     no further force or effect, and (ii) to release and discharge the other
     party and its respective directors, officers, employees, agents and
     representatives from and against any and all liabilities, costs,
     obligations, claims, damages and expenses of every kind and nature arising
     under, or in connection with the transactions contemplated, by the
     Investment Agreement.

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                                                                Mr. Robert Lange
                                                                 August 19, 1998
                                                                          Page 2

4)   Acknowledgement. Each of the Lindner Funds acknowledges and agrees:

     a)   It has received or obtained and had the opportunity to review copies
          of all reports and other materials which have been filed by the
          Company pursuant to the Securities Exchange Act of 1934 since the date
          of the Investment Agreement, including without limitation copies of
          Interleaf's 1998 Annual Report to Shareholders, Annual Report on Form
          10-K for the year ended March 31, 1998, Quarterly Report on Form 10-Q
          for the quarter ended June 30, 1998, and its Proxy Statement dated
          July 28, 1998.

     b)   It has had full and adequate opportunity to investigate the condition
          of the Company and its business, and they are satisfied with the
          results of its inquiries. Interleaf has provided to and discussed with
          the Lindner Funds such information as the Lindner Funds has requested
          (to the extent available) regarding the financial results of Interleaf
          for the quarter ended June 30,1998, and the current operations,
          financial condition and plans of Interleaf. Each of the Lindner Funds
          represents and warrants that, in selling the Series C Shares, it has
          not relied on any information or representations or warranties of
          Interleaf or its directors, officers or agents regarding the Company,
          its officers, financial condition, business and prospects, or the
          terms of its sale of the Series C Shares.

     c)   It is an "accredited investor" within the meaning of Rule 501 of
          Regulation D promulgated under the Securities Act of 1933, as amended.

     d)   It has full and sufficient power and authority and has obtained all
          approvals required, and has complied with all requirements and all
          reporting obligations applicable under the Federal securities laws,
          with respect to this transaction.

5)   Miscellaneous.

     a)   Each party will keep the terms, conditions and existence of this
          Letter Agreement strictly confidential, and not disclose such
          information to any person for any reason except to such of their
          respective accountants, attorneys and advisors to whom such disclosure
          is necessary in order to consummate this transaction, and who have
          agreed in writing to protect such confidentiality. Provided, that
          Interleaf may issue a press release or otherwise disclose the terms of
          this Agreement as and when Interleaf determines such disclosure is
          required under applicable securities laws.

     b)   As part of the Closing, the parties will execute such instruments of
          transfer, mutual releases and other documents and agreements as are
          necessary or appropriate in connection with this transaction.


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                                                                Mr. Robert Lange
                                                                 August 19, 1998
                                                                          Page 3

     c)   This Letter Agreement is the legal, valid and binding obligation of
          Interleaf and each of the Lindner Funds, enforceable in accordance
          with its terms. Provided, however, Interleaf's obligations are subject
          to approval of its Board of Directors, scheduled for August 24, 1998.

     d)   This Letter Agreement amends and, to the extent inconsistent with,
          supercedes the Investment Agreement. In the event of any conflict
          between the terms of this Letter Agreement and the terms of the
          Investment Agreement, the terms of this Letter Agreement shall
          control.

     e)   This Letter Agreement shall be governed by the laws of the
          Commonwealth of Massachusetts. Each party irrevocably consents to
          jurisdiction and venue in the appropriate state and federal courts
          closest to the other party's principal place of business and covenants
          to not assert forum non conveniens in any action between the parties.
          Each party agrees that, in the event it beaches its obligations
          hereunder, the other party shall be entitled to obtain specific
          performance or other equitable relief, in addition to its other
          remedies, and damages.

Please indicate the agreement of the Lindner Funds to the foregoing terms and
conditions by obtaining their authorized signatures where provided below.

I look forward to closing this transaction.

Very truly yours,

Interleaf, Inc.


By:  /s/ Jaime W. Ellertson
     -----------------------
     Jaime W. Ellertson, CEO

AGREED:

         Lindner Growth Fund               Lindner Dividend Fund


By:      /s/ Robert A. Lange               By:      /s/ Eric E. Ryback

Name:    Robert A. Lange                   Name:    Eric E. Ryback

Title:   Senior Vice President             Title:   President

Date:    August 21, 1998                   Date:    August 21, 1998