GUARANTY




EXHIBIT 10.6

EXECUTION COPY

GUARANTY

This GUARANTY (together with all amendments,
if any, from time to time hereto, this "Guaranty"), dated as of December 31,
2003, is made by and among COMMERCE ONE OPERATIONS, INC. (the "Guarantor"), a
Delaware corporation and wholly-owned subsidiary of Commerce One, Inc. (the
"Seller"), COMVEST INVESTMENT PARTNERS II , a Delaware limited liability company
("ComVest") and DCC VENTURES, LLC, a Nevada limited liability company ("DCC" and
together with ComVest, the "Purchasers").  Any capitalized terms used but not
defined herein shall have the meanings ascribed thereto in the Purchase
Agreement.   

W I T N E S S E T H:


WHEREAS,  the Seller has offered for sale to the
Purchasers, and the Purchasers have purchased from the Seller, (i) Senior
Secured Non-Convertible Promissory Notes of the Seller in the aggregate
principal amount of Five Million Dollars ($5,000,000) (the "Notes") and (ii)
Warrants to purchase shares of common stock, par value $.0001 per share, of the
Seller (the "Warrants") under the terms of the Purchase Agreement;

WHEREAS, under the terms and conditions of the Purchase
Agreement, the Purchasers  have purchased the Notes and Warrants dated the date
hereof and as set forth in Exhibits A and B, respectively, annexed
hereto and made a part hereof, with payment of the Notes and any other
obligations of Seller to the Purchasers, and each of them, to be secured as
provided for in the Purchase Agreement;

WHEREAS, under the terms and conditions of the Purchase
Agreement, in order to induce the Purchasers to purchase the Notes and Warrants,
the Guarantor agreed to execute and deliver to the Purchasers (i) this Guaranty,
pursuant to which the Guarantor shall agreed to guarantee the full repayment of
the Notes and all other obligations of the Seller under the Purchase Agreement
and other Closing Documents (the "Guaranteed Obligations"), and (ii) a Security
Agreement granting the Purchasers a first perfected priority lien and security
interest in the Collateral (as defined therein) to secure all of the Guarantor's
and the Seller's respective obligations under the Purchase Agreement, the Notes
and other Closing Documents, as set forth in more detail in the Security
Agreement (collectively, the "Obligations").

WHEREAS, Guarantor will derive actual, direct and indirect
economic benefits from the sale of the Notes and Warrants; and

WHEREAS, in order to induce the Purchasers to purchase the
Notes and Warrant and enter into the Purchase Agreement and other Closing
Documents, the Guarantor has agreed to guarantee payment of the Guaranteed
Obligations;

NOW, THEREFORE, in consideration of the premises and the
covenants hereinafter contained, it is agreed as follows:








1.Definitions.  Capitalized terms used herein
(including terms used in the Recitals) shall have the meanings assigned to them
in the Purchase Agreement, unless otherwise defined herein.

References to this "Guaranty" shall mean this Guaranty,
including all amendments, modifications and supplements and any annexes,
exhibits and schedules to any of the foregoing, and shall refer to this Guaranty
as the same may be in effect at the time such reference becomes operative.

2.The Guaranty.

2.1Guaranty of Obligations.  The Guarantor hereby
unconditionally guarantees to Purchasers and its successors, endorsees,
transferees and assigns, the prompt payment (whether at stated maturity, by
acceleration or otherwise) and performance of the Guaranteed Obligations.
Guarantor agrees that this Guaranty is a guaranty of payment and performance and
not of collection, and that their obligations under this Guaranty shall be
primary, absolute and unconditional, irrespective of, and unaffected
by:

(a)the genuineness, validity, regularity, enforceability
or any future amendment of, or change in this Guaranty, any other Closing
Document or any other agreement, document or instrument to which Guarantor is or
may become a party;

(b)the absence of any action to enforce this Guaranty or
any other Closing Document or the waiver or consent by Purchasers with respect
to any of the provisions thereof;

(c)the existence, value or condition of, or failure to
perfect the lien and security interest granted by Guarantor and Seller under the
Security Agreement, any Collateral for the Guaranteed Obligations or any action,
or the absence of any action, by Purchasers in respect thereof (including,
without limitation, the release of any such security);

(d)the insolvency of Purchasers; or

(e)any other action or circumstances which might
otherwise constitute a legal or equitable discharge or defense of a surety or
guarantor,



it being agreed by the Guarantor that its obligations under
this Guaranty shall not be discharged until the Satisfaction Date (as defined in
the Pledge Agreement).  The Guarantor shall be regarded, and shall be in the
same position, as principal debtor with respect to the Guaranteed Obligations.
The Guarantor agrees that any notice or directive given at any time to
Purchasers  which is inconsistent with the waiver in the immediately preceding
sentence shall be null and void and may be ignored by Purchasers, and, in
addition, may not be pleaded or introduced as evidence in any litigation
relating to this Guaranty for the reason that such pleading or introduction
would be at variance with the written terms of this Guaranty, unless Purchasers
have specifically agreed otherwise in writing.  It is agreed among the Guarantor
and Purchasers that the foregoing waivers are of the essence of the transactions
contemplated by the Closing



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Documents and that, but for this Guaranty and such
waivers, Purchaser would decline to enter into the Purchase Agreement and other
Closing Documents.
2.2Demand by Purchasers.  In addition to the terms
of the Guaranty set forth in Section 2.1 hereof, and in no manner imposing any
limitation on such terms, it is expressly understood and agreed that, if, at any
time, the outstanding principal amount of the Guaranteed Obligations (including
all accrued interest thereon) is declared to be immediately due and payable,
then Guarantor shall, without demand, pay to the Purchasers the entire
outstanding Guaranteed Obligations due and owing to such holders.  Payment by
Guarantor shall be made to Purchasers in immediately available Federal funds to
an account designated by Purchasers for the giving of notice to Purchasers or at
any other address that may be specified in writing from time to time by
Purchasers, and shall be credited and applied to the Guaranteed Obligations.

2.3Enforcement of Guaranty.  In no event shall
Purchasers have any obligation (although it is entitled, at its option) to
proceed against the Seller or any Collateral pledged to secure Guaranteed
Obligations before seeking satisfaction from the Guarantor, and Purchasers may
proceed, prior or subsequent to, or simultaneously with, the enforcement of
Purchasers' rights hereunder, to exercise any right or remedy which it may have
against any Collateral, as a result of any lien it may have as security for all
or any portion of the Guaranteed Obligations.

2.4Waiver.  In addition to the waivers contained
in Section 2.1 hereof, Guarantor waives, and agrees that it shall not at any
time insist upon, plead or in any manner whatever claim or take the benefit or
advantage of, any appraisal, valuation, stay, extension, marshaling of assets or
redemption laws, or exemption, whether now or at any time hereafter in force,
which may delay, prevent or otherwise affect the performance by Guarantor of its
Guaranteed Obligations under, or the enforcement by Purchasers of, this
Guaranty. Guarantor hereby waives diligence, presentment and demand (whether for
non-payment or protest or of acceptance, maturity, extension of time, change in
nature or form of the Guaranteed Obligations, acceptance of further security,
release of further security, composition or agreement arrived at as to the
amount of, or the terms of, the Guaranteed Obligations, notice of adverse change
in Seller's financial condition or any other fact which might increase the risk
to Guarantor) with respect to any of the Guaranteed Obligations or all other
demands whatsoever and waives the benefit of all provisions of law which are or
might be in conflict with the terms of this Guaranty.  Guarantor represents,
warrants and agrees that, as of the date of this Guaranty, its obligations under
this Guaranty are not subject to any offsets or defenses against Purchasers,
Seller or Guarantor of any kind.  Guarantor further agrees that its obligations
under this Guaranty shall not be subject to any counterclaims, offsets or
defenses against Purchasers, Seller or Guarantor of any kind which may arise in
the future.

2.5Benefit of Guaranty.  The provisions of this
Guaranty are for the benefit of Purchasers and their respective successors,
transferees, endorsees and assigns, and nothing herein contained shall impair
the obligations of Seller or the Guarantor under the Purchase Agreement and the
other Closing Documents.  In the event all or any part of the Guaranteed
Obligations are transferred, indorsed or assigned by Purchasers to any Person or
Persons, any reference to "Purchasers " herein shall be deemed to refer equally
to such Person or Persons.



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2.6Modification of Guaranteed Obligations, Etc.
The Guarantor hereby acknowledges and agrees that Purchasers may at any time or
from time to time, with or without the consent of, or notice to,
Guarantor:
(a)change or extend the manner, place or terms of payment
of, or renew or alter all or any portion of, the Guaranteed Obligations;

(b)take any action under or in respect of the Note or
Warrantin the exercise of any remedy, power or privilege contained therein or
available to it at law, equity or otherwise, or waive or refrain from exercising
any such remedies, powers or privileges;

(c)amend or modify, in any manner whatsoever, the Note or
Warrant;

(d)extend or waive the time for Seller's or Guarantor's
performance of, or compliance with, any term, covenant or agreement on its part
to be performed or observed under the Purchase Agreement or any other Closing
Documents, or waive such performance or compliance or consent to a failure of,
or departure from, such performance or compliance;

(e)take and hold Collateral of the Seller for the payment
of the Guaranteed Obligations guaranteed hereby or sell, exchange, release,
dispose of, or otherwise deal with, any property pledged, mortgaged or conveyed,
or in which Purchasers have been granted a lien, to secure any Guaranteed
Obligations;

(f)modify or terminate the terms of any intercreditor or
subordination agreement pursuant to which claims of other creditors of Guarantor
or Seller are subordinated to the claims of Purchasers; and/or

(g)apply any sums by whomever paid or however realized to
any amounts owing by Guarantor or Seller to Purchasers in such manner as
Purchasers shall reasonably determine in its discretion;



and Purchasers shall not incur any liability to Guarantor as
a result thereof, and no such action shall impair or release the Guaranteed
Obligations of Guarantor under this Guaranty.

2.7Reinstatement.  Until the Satisfaction Date,
this Guaranty shall remain in full force and effect and continue to be effective
should any petition be filed by or against Seller or Guarantor for liquidation
or reorganization, should Seller or Guarantor become insolvent or make an
assignment for the benefit of creditors or should a receiver or trustee be
appointed for all or any significant part of Seller's or Guarantor's, as the
case may be, assets, and shall continue to be effective or be reinstated, as the
case may be, if at any time payment and performance of the Guaranteed
Obligations, or any part thereof, is, pursuant to applicable law, rescinded or
reduced in amount, or must otherwise be restored or returned by Purchasers,
whether as a "voidable preference," "fraudulent conveyance," or otherwise, all
as though such payment or performance had not been made.  In the event that any
payment, or any part thereof, is rescinded, reduced, restored or returned, the
Guaranteed Obligations shall be reinstated and deemed reduced only by such
amount paid and not so rescinded, reduced, restored or returned.



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2.8Deferral of Subrogation, Etc.  Notwithstanding
anything to the contrary in this Guaranty, or in any other Closing Document, the
Guarantor hereby:
(a)expressly and irrevocably waives, on behalf of itself
and its successors and assigns (including any surety) until the Satisfaction
Date, any and all rights at law or in equity to subrogation, to reimbursement,
to exoneration, to contribution, to indemnification, to set off or to any other
rights that could accrue to a surety against a principal, to a guarantor against
a principal, to a guarantor against a maker or obligor, to an accommodation
party against the party accommodated, to a holder or transferee against a maker,
or to the holder of any claim against any Person, and which Guarantor may have
or hereafter acquire against Seller in connection with or as a result of
Guarantor's execution, delivery and/or performance of this Guaranty, or any
other documents to which Guarantor is a party or otherwise; and

(b)acknowledges and agrees (i) that this waiver is
intended to benefit Purchasers and shall not limit or otherwise effect any
Guarantor's liability hereunder or the enforceability of this Guaranty, and (ii)
that Purchasers  and its successors and assigns are intended third-party
beneficiaries of the waivers and agreements set forth in this Section 2.8 and
their rights under this Section 2.8 shall survive payment in full of the
Guaranteed Obligations.



2.9Election of Remedies.  If Purchasers may, under
applicable law, proceed to realize benefits under any of the Closing Documents
giving Purchasers a lien upon any Collateral owned by Guarantor or Seller,
either by judicial foreclosure or by non-judicial sale or enforcement,
Purchasers  may, at their sole option, determine which of such remedies or
rights it may pursue without affecting any of such rights and remedies under
this Guaranty.  If, in the exercise of any of its rights and remedies,
Purchasers shall forfeit any of their respective rights or remedies, including
its right to enter a deficiency judgment against Seller or Guarantor, whether
because of any applicable laws pertaining to "election of remedies" or the like,
Guarantor hereby consents to such action by Purchasers and waives any claim
based upon such action, even if such action by Purchasers shall result in a full
or partial loss of any rights of subrogation which Guarantor might otherwise
have had but for such action by Purchasers. Any election of remedies which
results in the denial or impairment of the right of Purchasers to seek a
deficiency judgment against Guarantor or Seller shall not impair Guarantor's
obligation to pay the full amount of the Guaranteed Obligations.  In the event
Purchasers shall bid at any foreclosure or trustee's sale or at any private sale
permitted by law or the Closing Documents, Purchasers may bid all or less than
the amount of the Guaranteed Obligations and the amount of such bid need not be
paid by Purchasers but shall be credited against the Guaranteed Obligations.  To
the extent permitted by applicable law, the amount of the successful bid at any
such sale shall be conclusively deemed to be the fair market value of the
collateral and the difference between such bid amount and the remaining balance
of the Guaranteed Obligations shall be conclusively deemed to be the amount of
the Guaranteed Obligations guaranteed under this Guaranty, notwithstanding that
any present or future law or court decision or ruling may have the effect of
reducing the amount of any deficiency claim to which Purchasers  might otherwise
be entitled but for such bidding at any such sale.



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2.10Funds Transfers.  If Guarantor shall engage in
any transaction as a result of which Seller is required to make a mandatory
prepayment with respect to the Guaranteed Obligations under the terms of the
Closing Documents, Guarantor shall deliver to the Seller an amount equal to the
mandatory prepayment required under the terms of the Closing Documents.

3.Deliveries.  In a form satisfactory to
Purchasers, Guarantor shall deliver to Purchasers concurrently with the
execution of this Guaranty, the other Closing Documents and other instruments,
certificates and documents as are required to be delivered by Guarantor to
Purchasers under the Purchase Agreement.

4.Representations and Warranties.  To induce
Purchasers to purchase the Notes and Warrants under the Purchase Agreement, the
Guarantor makes, to the extent applicable and as indicated in the Purchase
Agreement), the representations and warranties contained in the Purchase
Agreement, which, to the extent applicable to the Guarantor, are incorporated
herein by reference, to Purchasers, and which, to the extent applicable to the
Guarantor, shall survive the execution and delivery of this Guaranty. 

5.Further Assurances.  Guarantor agrees, upon the
written request of Purchasers, to execute and deliver to Purchasers, from time
to time, any additional instruments or documents reasonably considered necessary
by Purchasers to cause this Guaranty to be, become or remain valid and effective
in accordance with its terms.

6.Payments Free and Clear of Taxes.  All payments
required to be made by Guarantor hereunder shall be made to Purchasers free and
clear of, and without deduction for, any and all present and future taxes.  If
Guarantor shall be required by law to deduct any taxes from or in respect of any
sum payable hereunder, (a) the sum payable shall be increased as much as shall
be necessary so that after making all required deductions (including deductions
applicable to additional sums payable under this Section 6), Purchaser receive
an amount equal to the sum it would have received had no such deductions been
made, (b) Guarantor shall make such deductions, and (c) Guarantor shall pay the
full amount deducted to the relevant taxing or other authority in accordance
with applicable law. Within thirty (30) days after the date of any payment of
taxes, Guarantor shall furnish to Purchasers the original or a certified copy of
a receipt evidencing payment thereof.  Guarantor shall indemnify and, within ten
(10) days of demand therefor, pay Purchasers for the full amount of taxes
(including any taxes imposed by any jurisdiction on amounts payable under this
Section 6) paid by Purchasers in connection with the transactions contemplated
by this Guaranty, the Purchase Agreement and other Closing Documents (other than
income taxes), and any liability (including penalties, interest and expenses)
arising therefrom or with respect thereto, whether or not such taxes were
correctly or legally asserted.  Purchasers hereby agree to cooperate at
Guarantor's cost and expense with Guarantor's reasonable requests in any action
brought by Guarantor to contest the accuracy, applicability or legality of any
taxes so paid.

7.Other Terms.
7.1Entire Agreement.  This Guaranty, together with
the other Closing Documents, constitutes the entire agreement between the
parties with respect to the subject



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matter hereof and supersedes all prior
agreements relating to a guaranty of the Notes and/or the Guaranteed
Obligations.
7.2Headings.  The headings in this Guaranty are
for convenience of reference only and are not part of the substance of this
Guaranty.

7.3Severability.  Whenever possible, each
provision of this Guaranty shall be interpreted in such a manner to be effective
and valid under applicable law, but if any provision of this Guaranty shall be
prohibited by or invalid under applicable law, such provision shall be
ineffective to the extent of such prohibition or invalidity, without
invalidating the remainder of such provision or the remaining provisions of this
Guaranty.

7.4Notices.  Whenever it is provided herein that
any notice, demand, request, consent, approval, declaration or other
communication shall or may be given to or served upon any of the parties by any
other party, or whenever any of the parties desires to give or serve upon
another any such communication with respect to this Guaranty, each such notice,
demand, request, consent, approval, declaration or other communication shall be
in writing and shall be addressed to the party to be notified at the address set
forth in the Purchase Agreement (or such other address as may be substituted by
notice given in the manner required by the Purchase Agreement), and given in the
manner required by Section 14(e) Purchase Agreement.

7.5Successors and Assigns.  This Guaranty and all
obligations of Guarantor hereunder shall be binding upon the successors and
assigns of Guarantor (including a debtor-in-possession on behalf of such
Guarantor) and shall, together with the rights and remedies of Purchasers
hereunder, inure to the benefit of Purchasers, all future holders of any
instrument evidencing any of the Obligations and their respective successors and
assigns.  No sales of participations, other sales, assignments, transfers or
other dispositions of any agreement governing or instrument evidencing the
Guaranteed Obligations or any portion thereof or interest therein shall in any
manner affect the rights of Purchasers hereunder.  Guarantor may not assign,
sell, hypothecate or otherwise transfer any interest in or obligation under this
Guaranty.

7.6No Waiver; Cumulative Remedies; Amendments.
Purchasers  shall not by any act, delay, omission or otherwise be deemed to have
waived any of its rights or remedies hereunder, and no waiver shall be valid
unless in writing, signed by Purchasers in accordance with Section 9 of the
Security Agreement and then only to the extent therein set forth.  A waiver by
Purchasers of any right or remedy hereunder on any one occasion shall not be
construed as a bar to any right or remedy which Purchasers would otherwise have
had on any future occasion.  No failure to exercise nor any delay in exercising
on the part of Purchasers, any right, power or privilege hereunder, shall
operate as a waiver thereof, nor shall any single or partial exercise of any
right, power or privilege hereunder preclude any other or future exercise
thereof or the exercise of any other right, power or privilege.  The rights and
remedies hereunder provided are cumulative and may be exercised singly or
concurrently, and are not exclusive of any rights and remedies provided by law.
None of the terms or provisions of this Guaranty may be waived, altered,
modified, supplemented or amended except by an instrument in writing, duly
executed by Purchasers (in accordance with Section 9 of the Security Agreement)
and Guarantor.



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7.7Termination.  This Guaranty is a continuing
guaranty and shall remain in full force and effect until the Satisfaction Date.
Upon payment and performance in full of the Guaranteed Obligations, Purchasers
shall deliver to Guarantor such documents as Guarantor may reasonably request to
evidence such termination.

7.8Counterparts.  This Guaranty may be executed in
any number of separate counterparts, each of which shall collectively and
separately constitute one agreement.

7.9Limitation on Guaranteed Obligations.
Notwithstanding any provision herein contained to the contrary, Guarantor's
liability hereunder shall be limited to an amount not to exceed the aggregate
principal amount of the Note plus all accrued interest thereon.

8.Governing Law.  This Guaranty shall be governed
by, construed under and interpreted and enforced in accordance with laws of the
State of New York, without giving effect to principles of choice of law.  Any
action or proceeding arising out of or relating to this Guaranty shall be
commenced in a federal or state court having competent jurisdiction in the State
of New York, and for the purpose of any such action or proceeding, each of the
parties and any assignees thereof submits to the personal jurisdiction of the
State of New York.  The parties hereby irrevocably consents to the exclusive
personal jurisdiction of any state or federal court for New York County in the
State of New York or the Southern District of New York.  The parties hereby
waive any objection to venue and any objection based on a more convenient forum
in any action instituted under this Guaranty.     

9.Security.  To secure payment of Guarantor's
obligations under this Guaranty, concurrently with the execution of this
Guaranty, Guarantor has entered into a Security Agreement pursuant to which
Guarantor and Seller have granted to Purchasers a security interest in the
Collateral and Guarantor has entered into a Pledge Agreement pursuant to which
the Guarantor has pledged  the Perfect Commerce Note to Purchasers.


[SIGNATURE PAGES FOLLOW]



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IN WITNESS WHEREOF, the parties hereto have executed and
delivered this Guaranty as of the date first above written.


	 	
COMMERCE ONE OPERATIONS, INC.


By:  /s/ Mark B. Hoffman

       Name:

       Title:


	 	
COMVEST INVESTMENT PARTNERS II LLC


By:  /s/ Harold Blue

       Name:

        Title:

	 	

DCC VENTURES, LLC


By:   /s/ Michael T. Davies

       Name: Michael T. Davies

       Title: Secretary and Treasurer





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