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                                                                    Exhibit 10.4

                             UNCONDITIONAL GUARANTY

     For and in consideration of certain loans by SILICON VALLEY BANK, a
California-chartered bank, with its principal place of business at 3003 Tasman
Drive, Santa Clara, California 95054 and with a loan production office located
at Five Radnor Corporate Center, 100 Matsonford Road, Suite 555, Radnor,
Pennsylvania 19087 ("Bank") to VOXWARE, INC., a Delaware corporation
(hereinafter, the "Borrower"), which loans were made pursuant to a certain Loan
and Security Agreement between Borrower and Bank dated December 29, 2003, as
may be amended from time to time (hereinafter, the "Agreement"), the undersigned
guarantor CROSS ATLANTIC TECHNOLOGY FUND II, L.P., a Delaware limited
partnership with its principal office at Five Radnor Corporate Center, Suite 555
1000 Matsonford Road, Radnor, Pennsylvania("Guarantor"), hereby unconditionally
and irrevocably guarantees the prompt and complete payment of all amounts that
Borrower owes to Bank and performance by Borrower of the Agreement and any other
agreements now existing or hereafter arising between Borrower and Bank, as each
may be amended from time to time (collectively referred to as the "Agreements"),
in strict accordance with their respective terms, except that the total amount
recoverable under this Unconditional Guaranty shall be limited to an amount not
greater than the sum of: (i) twenty-five percent (25.0%) (hereinafter, the
"Guarantor's Percentage") of the principal balance outstanding under the
Obligations (as defined in the Agreement), up to but not exceeding Five Hundred
Thousand Dollars ($500,000.00) in principal in the aggregate, plus (ii) the
Guarantor's Percentage of the interest outstanding under the Obligations (each
as defined in the Agreement at the rates provided in the Agreement (including,
without limitation, any default rate described in the Agreement which may be
applied at a later date)), plus (iii) the reasonable costs of collection to
enforce the Bank's rights and remedies under this Guaranty.

     1.    Subject to the limitations set forth above, if Borrower does not
perform its obligations under the Agreement and after the expiration of all
applicable cure periods under the Agreement, Guarantor will pay, within fifteen
(15) days of the receipt of written notice from the Bank, all amounts due
(including, without limitation, all principal, interest, and fees) and satisfy
all Borrower's obligations under the Agreements.

     2.    These obligations are independent of Borrower's obligations and
separate actions may be brought against Guarantor (whether action is brought
against Borrower or whether Borrower is joined in the action).

     3.    Bank may, without notice to Guarantor and without affecting
Guarantor's obligations under this Guaranty: (a) renew, extend, or otherwise
change the terms of the Agreements; (b) take security for the payment of the
Agreements; (c) exchange, enforce, waive and release any security granted under
the Agreement; and (d) apply the security granted under the Agreement and direct
its sale as Bank, in its discretion, chooses.

     4.    Guarantor agrees that in the event the loan arrangement dated
February 15, 2004, entered into between the Bank and Guarantor for bridge
financing of capital calls is terminated for any reason, the Guarantor shall
immediately secure the Obligations under this Guaranty with collateral
acceptable to Bank.

     5.    Guarantor waives:

           (a) Any right to require Bank to: (i) proceed against Borrower or any
     other person; (ii) proceed against or exhaust any security; or (iii) pursue
     any other remedy. Bank may exercise or not exercise any right or remedy it
     has against Borrower or any security it holds (including the right to
     foreclose by judicial or non- judicial sale) without affecting Guarantor's
     liability.

           (b) Any defenses from disability or other defense of Borrower or from
     the cessation of Borrowers liabilities.

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           (c) Any setoff, defense or counterclaim against Bank.

           (d) Any defense from the absence, impairment or loss of any right of
     reimbursement or subrogation or any other rights against Borrower. Until
     Borrower's obligations to Bank have been paid, Guarantor will not exercise
     any right of subrogation or reimbursement or subrogation or other rights
     against Borrower.

           (e) Any right to enforce any remedy that Bank has against Borrower,
     until Borrower's obligations to Bank have been paid and the termination of
     Bank's commitment to lend under the Agreement.

           (f) Any rights to participate in any security held by Bank until
     Borrower's obligation to Bank have been paid and the termination of Bank's
     commitment to lend under the Agreement.

           (g) Any demands for performance, notices of nonperformance or of new
     or additional indebtedness. Guarantor is responsible for being and keeping
     itself informed of Borrower's financial condition. Unless Guarantor
     requests particular information, Bank has no duty to provide information to
     Guarantor.

     6. Guarantor acknowledges that, to the extent Guarantor has or may have
rights of subrogation or reimbursement against Borrower for claims arising out
of this Guaranty, those rights may be impaired or destroyed if Bank elects to
proceed against any real property security of Borrower by non-judicial
foreclosure. That impairment or destruction could, under certain judicial cases
and based on equitable principles of estoppel, give rise to a defense by
Guarantor against its obligations under this Guaranty. Guarantor waives that
defense and any others arising from Bank's election to pursue non-judicial
foreclosure.

     7. If Borrower becomes insolvent or is adjudicated bankrupt or files a
petition for reorganization or similar relief under the United States Bankruptcy
Code, or if a petition is filed against Borrower and/or any obligation under the
Agreements is terminated or rejected, or any obligation of Borrower is modified
or if Borrower's obligations are avoided Guarantor's liability will not be
affected and its liability will continue. If Bank must return any payment
because of the insolvency, bankruptcy or reorganization of Borrower, Guarantor
or any other guarantor, this Guaranty will remain effective or be reinstated.

     8. Guarantor subordinates any indebtedness of Borrower it holds to Bank;
and Guarantor will collect, enforce and receive payments as Bank's trustee and
will pay Bank those payments without reducing or affecting its liability under
this Guaranty.

     9. Guarantor will pay Bank's reasonable attorneys' fees and other costs and
expenses incurred enforcing this Guaranty. This Guaranty may not be waived,
revoked or amended without Bank's and Guarantor's prior written consent. If any
provision of this Guaranty is unenforceable, all other provisions remain
effective. This Guaranty represents the entire agreement among the parties about
this Guaranty. No prior dealings, no usage of trade, and no parol or extrinsic
evidence may supplement or vary this Guaranty. Bank may assign this Guaranty.
This Guaranty benefits Bank, its successors and assigns. This Guaranty is in
addition to any other guaranties Bank obtains.

     10. Guarantor represents and warrants that (i) it has taken all action
necessary to authorize execute, deliver and perform this Guaranty; (ii)
execution, delivery and performance of this Guaranty do not conflict with any
organizational documents or agreements to which it is a party; and (iii) this
Guaranty is a valid and binding obligation, enforceable against Guarantor
according to its terms.

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     11. Guarantor will do all of the following:

          (a) Maintain its legal existence, remain in good standing in Delaware,
     and continue to qualify in each jurisdiction in which the failure to
     qualify could have a material adverse effect on the financial condition,
     operations or business. Maintain all licenses, approvals, and agreements,
     the loss of which could have a material adverse effect on its financial
     condition, operations or business.

          (b) Comply with all statutes and regulations if non-compliance could
     adversely affect its financial condition, operations or business, in any
     material respect.

          (c) Execute other instruments and take action Bank reasonably requests
     to effect the purposes of this Agreement.

     12. Guarantor hereby grants to Bank, a lien, security interest and right of
setoff as security for all obligations to Bank, whether now existing or
hereafter arising upon and against all deposits, credits, collateral and
property, now or hereafter in the possession, custody, safekeeping or control of
Bank or any entity under the control of Bank (including a Bank subsidiary) or in
transit to any of them. At any time after the occurrence and during the
continuance of an Event of Default (as defined in the Agreement), without demand
or notice, Bank may set off the same or any part thereof and apply the same to
any liability or obligation of Guarantor then due and payable and regardless of
the adequacy of any other collateral securing the Obligations. ANY AND ALL
RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY
OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF
SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF THE
GUARANTOR, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

     13. Massachusetts law governs this Guaranty without regard to principles of
conflicts of law. Guarantor and Bank each submit to the exclusive jurisdiction
of the State and Federal courts in Massachusetts; provided, however, that if for
any reason Bank cannot avail itself of such courts in the Commonwealth of
Massachusetts, Guarantor accepts jurisdiction of the courts and venue in Santa
Clara County, California. NOTWITHSTANDING THE FOREGOING, THE BANK SHALL HAVE THE
RIGHT TO BRING ANY ACTION OR PROCEEDING AGAINST THE GUARANTOR OR ITS PROPERTY IN
THE COURTS OF ANY OTHER JURISDICTION WHICH THE BANK DEEMS NECESSARY OR
APPROPRIATE IN ORDER TO REALIZE ON THE COLLATERAL OR TO OTHERWISE ENFORCE THE
BANK'S RIGHTS AGAINST THE GUARANTOR OR ITS PROPERTY. GUARANTOR AND BANK EACH
WAIVE THEIR RIGHT TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION ARISING OUT OF
OR BASED UPON THIS AGREEMENT, THE LOAN DOCUMENTS OR ANY CONTEMPLATED
TRANSACTION, INCLUDING CONTRACT, TORT, BREACH OF DUTY AND ALL OTHER CLAIMS. THIS
WAIVER IS A MATERIAL INDUCEMENT FOR BOTH PARTIES TO ENTER INTO THIS AGREEMENT.
EACH PARTY HAS REVIEWED THIS WAIVER WITH ITS COUNSEL.

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         IN WITNESS WHEREOF, the undersigned Guarantor has executed this
Guaranty as an instrument under seal under the laws of the Commonwealth of
Massachusetts, as of this 29th day of December, 2003.

                                  CROSS ATLANTIC TECHNOLOGY FUND II, L.P.
                                  By: XATF Management II, L.P
                                  Its General Partner
                                  By: Cross Atlantic Capital Partners II, Inc.
                                  Its General Partner

                                  By:____________________________________

                                  Title:__________________________________

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