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                                                                   EXHIBIT 10.17

                              SYMPOSIUM CORPORATION
                                 410 PARK AVENUE
                                    SUITE 830
                            NEW YORK, NEW YORK 10022



                                          April 24, 2000

Lancer Offshore Inc.
Kaya Flamboyan 9
Curacao, Netherlands Antilles

Capital Research, Ltd.
27241 Paseo Peregrino
San Juan Capo, California  92675

Mr. Gary Herman
c/o GHM, Inc.
74 Trinity Place, 20th Floor
New York, New York  10006

Mr. Joseph Giamanco
c/o GHM, Inc.
74 Trinity Place, 20th Floor
New York, New York  10006

Gentlemen:

      Reference is made to the Certificate of Designation (the "Certificate")
creating the series of preferred stock of Symposium Corporation, a Delaware
corporation (the "Company"), designated as the Series C Preferred Stock, par
value $.001 per share (the "Series C Shares"), and the Term Sheet (the "Term
Sheet") describing the terms upon which the Series C Shares were offered and
sold to each of you. The Certificate and the Term Sheet are hereinafter
collectively referred to as the "Documents."

      The Documents provide that if the Series C Shares are not redeemed in full
within 180 days following issuance, such 180th day being July 26, 2000 (the
"Series C Trigger Date"): (A) the price at which the Series C Shares are
convertible into shares of the Company's Common Stock will be reduced from $2.00
per share to $0.25 per share and the Company will be required to issue to the
holders of the Series C Shares, monthly in advance until the Series C Shares are
redeemed in full, five-year warrants to purchase 370,244 shares of Common Stock
at an exercise price of $0.25 per share (the "Warrants").
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      The Company and the Holders (severally and not jointly) hereby agree as
follows:

      1. Notwithstanding any provision of the Documents to the contrary, the
reduction of the conversion price of the Series C Shares referred to in clause
(a) above and the requirement that the Company issue Warrants referred to in
clause (b) above will not become effective if the Company redeems the Series C
Shares in full on or before December 26, 2000. If the Company fails to redeem
the Series C Shares in full on or prior to December 26, 2000, then the reduction
of the conversion price of the Series C Shares referred to in clause (a) above
and the requirement that the Company issue the Warrants referred to in clause
(b) above will become effective as of December 27, 2000 and will remain
effective thereafter unless and until the Series C Shares are redeemed in full.

      2. Notwithstanding the provisions of the Documents to the contrary, the
payment date for all accrued and unpaid dividends on the Series C Shares through
April 26, 2000 will be extended to December 26, 2000. The Holders hereby waive
any default arising out of or relating to the Company's failure to pay such
dividends on any dividend payment date (as defined in the Documents) occurring
prior to the date hereof or at any time prior to December 26, 2000.

      3. In consideration for the agreements of each Holder set forth herein,
the Company hereby agrees as follows: (a) the Company will issue to each Holder,
promptly following the execution and delivery of this Letter, one share of
Common Stock for each $3.00 of Stated Value of Series C Shares held by such
Holder (rounded upward to the nearest whole share of Common Stock); and (b) if
such Holder converts the Series C Shares into shares of Common Stock during the
period commencing on the date of execution and delivery of this Letter by such
Holder and ending on December 26, 2000, the Company will issue to such Holder
without additional consideration, concurrently with such conversion (and in
addition to the number of shares of Common Stock issuable upon such conversion),
the number of additional shares of Common Stock equal to the excess of: (i) the
number of shares of Common Stock issuable upon such conversion assuming an
effective conversion price of $1.00 per share; over (ii) the number of shares of
Common Stock issuable upon such conversion at the conversion price then in
effect pursuant to the Documents. The number of shares issuable pursuant to
clause (i) and the conversion price specified therein shall be subject to
adjustment in the manner set forth in the Documents upon the occurrence of any
of the events described therein. The shares issuable pursuant to this paragraph
3 are hereinafter referred to collectively as the "Additional Shares." All
Additional Shares issuable to the Holders will be entitled to the same
registration rights as the shares of Common Stock issuable to the Holders upon
conversion of the Series C Shares pursuant to the Documents.

      4. The Company also agrees to pay a fee to Capital Research Ltd. equal to
$242,000, such fee to be payable, at the Company's option, in cash, or in shares
of Common Stock having a deemed value of $0.50 per share. Accordingly, if the
entire fee were paid in shares of Common Stock, the Company would be required to
issue 484,000 shares of Common Stock to pay such fee in full.

      5. Except as expressly provided herein, the Documents will remain in full
force and effect as originally executed and delivered by the parties hereto.
This Letter supersedes any prior
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understanding or agreement, written or oral, among the parties hereto relating
to the subject matter hereof.

      6. Each of the Holders each hereby severally represents to the Company, on
behalf of itself, that such Holder is (and on each date of issuance of such
Additional Shares will be) an "accredited investor" within the meaning of
Regulation D, as promulgated by the Securities and Exchange Commission pursuant
to the Securities Act of 1933, as amended (the "Act"), and has such knowledge
and experience in financial and business matters that it is capable of
evaluating the merits and risks of an investment in the Additional Shares; that
such Holder is acquiring the Additional Shares to be issued to such Holder for
investment and without a view to the sale, assignment, transfer or other
distribution thereof; the Additional Shares may not be offered for sale, sold or
otherwise transferred except pursuant to an effective registration statement
under the Act and in compliance with the applicable securities laws of any state
or other jurisdiction, or pursuant to an opinion of counsel satisfactory to the
Company that such registration is not required and such compliance has been
obtained. The Company may affix an appropriate legend to any certificate(s)
representing the Additional Shares to reflect the foregoing.

            7. This Letter will be governed by the laws of the State of New York
applicable to contracts made and to be performed entirely within such State. Any
claims or disputes relating in any way to this Agreement shall be submitted to
the New York State courts or the United States District Court for the Southern
District of New York. The parties hereby consent to such venue and the personal
jurisdiction of such courts and agree not to contest such venue or assert any
claim to move the claim or dispute to another venue or forum.

            If the foregoing correctly sets forth our understanding, please so
indicate by signing an enclosed counterpart of this Letter and returning it to
the undersigned, whereupon it will constitute a binding agreement between us.
The failure of any one or more Holders to execute a counterpart of this Letter
will not affect the obligations of the Company or of any one or more Holders
signing counterparts hereof. This Letter may be executed in counterparts and by
the parties hereto in separate counterparts, each of which shall constitute an
original and all of which together shall constitute one and the same agreement.

                                    Very truly yours,

                                    SYMPOSIUM CORPORATION


                                    By: /s/ Ronald Altbach
                                       ----------------------------------
                                       Ronald Altbach
                                        Chairman of the Board and Chief
                                        Executive Officer




Accepted and agreed to as of
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the date first above written:

LANCER OFFSHORE, INC.


By: /s/ M. Lauer
    --------------------------------



CAPITAL RESEARCH, LTD.


By: /s/ Bruce D. Cowen
    -------------------------------


 /s/ Joseph Giamanco
-----------------------------------
JOSEPH GIAMANCO


 /s/ Gary Herman
-----------------------------------
GARY HERMAN





[Signature Page of Letter Agreement, dated as of April 24, 2000, among Symposium
Corporation and the Holders of the Series C Preferred Shares]