<PAGE>

                                                                    EXHIBIT 10.1

SILICON VALLEY BANK

                           AMENDMENT TO LOAN AGREEMENT

BORROWER:      ONYX SOFTWARE CORPORATION

DATE:          MARCH 28, 2006

      THIS AMENDMENT TO LOAN DOCUMENTS (the "Amendment") is entered into between
Silicon Valley Bank ("Silicon") and the borrower named above ("Borrower").

      The Parties agree to amend the Loan and Security Agreement between them,
dated February 14, 2002 (as otherwise amended, if at all, the "Loan Agreement"),
as follows, effective as of the date hereof. (Capitalized terms used but not
defined in this Amendment shall have the meanings set forth in the Loan
Agreement.)

      1. MODIFIED ACQUISITION PROVISION. The following is hereby added at the
end of Section 5.5 of the Loan Agreement and shall read as follows:

         Notwithstanding anything to the contrary in this Section 5.5, Borrower
         will be permitted to merge or consolidate with another corporation or
         entity without the prior written consent of Silicon if such acquisition
         satisfies each of the following requirements: (a) the acquired entity
         is in the same or similar line of business as Borrower, (b) the
         acquisition is a non-hostile acquisition (as determined by Silicon in
         its good faith business judgment), (c) no Default or Event of Default
         exists both before such acquisition and after giving effect to such
         acquisition, (d) the acquired entity must show a positive trailing six
         month EBITDA (earnings before interest, taxes, depreciation and other
         non-cash amortization expenses, determined in accordance with generally
         accepted accounting principles, consistently applied), (e) the total
         cash consideration paid by Borrower in each such acquisition cannot
         exceed $5,000,000 and (f) the Borrower must be the surviving
         corporation of such merger or consolidation.

      2. MODIFIED PREPAYMENT PROVISION. Section 6.2 of the Loan Agreement is
hereby amended to read as follows:

         6.2 EARLY TERMINATION. This Agreement may be terminated prior to the
         Maturity Date as follows: (i) by Borrower, effective three Business
         Days after written notice of termination is given to Silicon; or (ii)
         by Silicon at any time after the occurrence of an Event of Default,
         without notice, effective immediately. If this Agreement is terminated
         by Borrower or by

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

         Silicon under this Section 6.2, Borrower shall pay to Silicon a
         termination fee in an amount equal to the following: (a) 1.5% of the
         Maximum Credit Limit if terminated before June 30, 2006; (b) 1.3125% of
         the Maximum Credit Limit if terminated after June 30, 2006 but before
         September 30, 2006; (c) 1.125% of the Maximum Credit Limit if
         terminated after September 30, 2006 but before December 31, 2006; (d)
         0.9375% of the Maximum Credit Limit if terminated after December 31,
         2006 but before March 31, 2007; (e) 0.75% of the Maximum Credit Limit
         if terminated after March 31, 2007 but before June 30, 2007; (f)
         0.5625% of the Maximum Credit Limit if terminated after June 30, 2007
         but before September 30, 2007; (g) 0.375% of the Maximum Credit Limit
         if terminated after September 30, 2007 but before December 31, 2007;
         and (h) 0.1875% of the Maximum Credit Limit if terminated after
         December 31, 2007 but before the Maturity Date. Notwithstanding the
         foregoing, no termination fee shall be charged if the credit facility
         hereunder is replaced with a new facility from another division of
         Silicon Valley Bank. The termination fee shall be due and payable on
         the effective date of termination and thereafter shall bear interest at
         a rate equal to the highest rate applicable to any of the Obligations.

      3. MODIFIED AUDIT PROVISION. The following sentence is hereby added after
the first sentence of Section 5.4 of the Loan Agreement and shall read as
follows:

         The parties contemplate that such audits will be performed no more
         frequently than annually, but nothing herein restricts Silicon's right
         to conduct such audits more frequently if (i) Silicon believes that it
         is advisable to do so in Silicon's good faith business judgment, or
         (ii) Silicon believes in good faith that a Default or Event of Default
         has occurred.

Moreover, the charges for such inspections and audits shall be $750 per person
per day (or such higher amount as shall represent Silicon's then current
standard charge for the same), plus reasonable out of pocket expenses.

      4. ADDING DEFINITION OF FOREIGN RECEIVABLES. Subclause (viii) of the
Minimum Eligibility Requirements set forth in the definition of "Eligible
Receivables" set forth in Section 8 of the Loan Agreement is hereby amended to
read as follows:

         (viii) the Receivable must not be owing from an Account Debtor located
         outside the United States or Canada (each a "Foreign Receivable")
         (unless pre-approved by Silicon in its discretion in writing, or backed
         by a letter of credit satisfactory to Silicon, or FCIA insured
         satisfactory to Silicon; provided, however, such pre-approval is not
         required provided the Foreign Receivable is an otherwise Eligible
         Receivable and is within the Foreign Receivables Sublimit),

      5. MODIFIED CREDIT LIMIT. Section 1 of the Schedule to Loan and Security
Agreement, entitled "Credit Limit," is hereby amended to read as follows:

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

         1. CREDIT LIMIT
            (Section 1.1):    An amount equal to the sum of 1 and 2 below:

                              1. Term Loan. An amount equal to the unpaid
                              principal balance from time to time outstanding of
                              the Loan ("Term Loan") previously made by Silicon,
                              the current principal balance of which is
                              $180,555.53. The Term Loan shall be used to
                              refinance the Borrower's Cisco Voice Over IP
                              Network. Any portion of the Term Loan, once
                              repaid, cannot be reborrowed.

                              As used in this Agreement, the word "Loans"
                              includes the Term Loan and the Revolving Loans.

                              2. Revolving Loans. An amount not to exceed the
                              following:

                                 (A) The lesser of:

                                     (i)   $8,000,000 at any one time
                                           outstanding (the "Maximum Credit
                                           Limit"), or

                                     (ii)  (a) or (b) below, whichever is
                                           applicable:

                                           (a)   the sum of (I) and (II) below
                                                 (the "Borrowing Base"):

                                           (I)   80% (an "Advance Rate") of the
                                                 amount of Borrower's Eligible
                                                 Receivables (as defined in
                                                 Section 8 above), plus

                                           (II)  80% of Borrower's Foreign
                                                 Receivables (that are otherwise
                                                 Eligible Receivables except for
                                                 the Account Debtor being
                                                 located outside the United
                                                 States or

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

                                                 Canada and which have not been
                                                 pre-approved by Silicon in
                                                 writing, are not backed by a
                                                 letter of credit satisfactory
                                                 to Silicon or are not FCIA
                                                 insured satisfactory to
                                                 Silicon) that are billed and
                                                 collected within the United
                                                 States, up to a maximum of
                                                 $2,500,000.

                                           OR

                                           (b)   Loans in the aggregate
                                                 principal amount outstanding of
                                                 not more than $8,000,000 (the
                                                 "Non-Formula Loan").

                                 Loans will be made pursuant to subclause 2(A)
                                 (ii)(b) above only if, and as long as, Borrower
                                 maintains, at all times, unrestricted cash in
                                 accounts maintained at Silicon of at least
                                 $12,500,000 (the "Minimum Cash On Hand
                                 Requirement"). At all other times, Loans will
                                 be made pursuant to subclause 2(A)(ii)(a)
                                 above.

                                 Notwithstanding the foregoing, Silicon may, in
                                 its sole discretion, make Loans to Borrower
                                 from time to time which exceed the limitations
                                 on borrowing against Eligible Receivables as
                                 set forth in subparagraph 2(A)(ii)(a) above
                                 (the "Overadvance Loans") which shall be
                                 secured by securities and investments of
                                 Borrower maintained with SVB Securities. The
                                 aggregate outstanding Overadvance Loans shall
                                 not at anytime exceed $500,000. Moreover, the
                                 aggregate outstanding Loans, including any
                                 Overadvance Loans, shall not at any time

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

                                 exceed the Maximum Credit Limit. This paragraph
                                 shall not apply at all times that Borrower
                                 satisfies the Minimum Cash On Hand Requirement.

                              minus

                              (B) the amount of all outstanding Letters of
                              Credit (including drawn but unreimbursed Letters
                              of Credit), and minus the FX Reserve, and minus
                              all amounts for Cash Management Services utilized
                              under the Cash Management Services Sublimit.

                              Silicon may, from time to time, modify the Advance
                              Rates, in its good faith business judgment, upon
                              notice to the Borrower, based on changes in
                              collection experience with respect to Receivables
                              or other issues or factors relating to the
                              Receivables or other Collateral.

         LETTER OF CREDIT
         SUBLIMIT
         (Section 1.6):       An amount equal to (A) the lesser of the Maximum
                              Credit Limit or the Borrowing Base or the Non-
                              Formula Loan (whichever is applicable), minus (B)
                              the FX Reserve, and minus (C) all amounts for Cash
                              Management Services utilized under the Cash
                              Management Services Sublimit, and minus (D) all
                              outstanding Loans; provided that the total of all
                              outstanding Letters of Credit (including drawn but
                              unreimbursed Letters of Credit), and the FX
                              Reserve, and all amounts for Cash Management
                              Services utilized under the Cash Management
                              Services Sublimit may not exceed $8,000,000.

         CASH MANAGEMENT
         SUBLIMIT:            An amount equal to (A) the lesser of the Maximum
                              Credit Limit or the Borrowing Base or the Non-
                              Formula Loan (whichever is applicable), minus (B)
                              the amount of all outstanding Letters of Credit
                              (including drawn but unreimbursed Letters of
                              Credit), and minus (C) the FX Reserve, and minus
                              (D) all outstanding Loans; provided that the total
                              of all outstanding Letters of Credit (including
                              drawn but unreimbursed Letters of Credit), and the
                              FX Reserve, and all amounts for Cash

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

                              Management Services utilized under the Cash
                              Management Services Sublimit may not exceed
                              $8,000,000.

         CASH MANAGEMENT
         SERVICES:            Borrower may use up to the Cash Management
                              Sublimit above, for Silicon's Cash Management
                              Services (as defined below), including, merchant
                              services, business credit card, ACH and other
                              services identified in the cash management
                              services agreement related to such service (the
                              "Cash Management Services"). Silicon may charge to
                              Borrower's Loan account, any amounts that may
                              become due or owing to Silicon in connection with
                              the Cash Management Services.  Borrower agrees to
                              execute and deliver to Silicon all standard form
                              applications and agreements of Silicon in
                              connection with the Cash Management Services, and,
                              without limiting any of the terms of such
                              applications and agreements, Borrower will pay all
                              standard fees and charges of Silicon in connection
                              with the Cash Management Services. The Cash
                              Management Services shall terminate on the
                              Maturity Date.

         FOREIGN EXCHANGE
         CONTRACT SUBLIMIT:   An amount equal to (A) the lesser of the Maximum
                              Credit Limit or the Borrowing Base or the Non-
                              Formula Loan (whichever is applicable), minus (B)
                              the amount of all outstanding Letters of Credit
                              (including drawn but unreimbursed Letters of
                              Credit), and minus (C) all amounts for Cash
                              Management Services utilized under the Cash
                              Management Services Sublimit, and minus (D) all
                              outstanding Loans; provided that the total of all
                              outstanding Letters of Credit (including drawn but
                              unreimbursed Letters of Credit), and the FX
                              Reserve, and all amounts for Cash Management
                              Services utilized under the Cash Management
                              Services Sublimit may not exceed $8,000,000.

         FX RESERVE:          Borrower may enter into foreign exchange forward
                              contracts with Silicon, on its standard forms,
                              under which Borrower commits to purchase from or
                              sell to Silicon a set amount of foreign currency
                              more than one business day after the contract date
                              (the "FX Forward Contracts"); provided that (1) at
                              the time the FX Forward Contract is entered into
                              Borrower has Loans available to it under this
                              Agreement in an amount at

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

                              least equal to 10% of the amount of the FX Forward
                              Contract; and (2) the total FX Forward Contracts
                              at any one time outstanding may not exceed 10
                              times the amount of the FX Sublimit set forth
                              above. The "FX Reserve" shall be a reserve (which
                              shall be in addition to all other reserves) in an
                              amount equal to 10% of the total FX Forward
                              Contracts from time to time outstanding. Silicon
                              may, in its discretion, terminate the FX Forward
                              Contracts at any time that an Event of Default
                              occurs and is continuing. Borrower shall execute
                              all standard form applications and agreements of
                              Silicon in connection with the FX Forward
                              Contracts, and without limiting any of the terms
                              of such applications and agreements, Borrower
                              shall pay all standard fees and charges of Silicon
                              in connection with the FX Forward Contracts.

      6. MODIFIED INTEREST RATE. The Interest Rate set forth in Section 2 of the
Schedule to Loan and Security Agreement is hereby amended to read as follows:

         INTEREST RATE (Section 1.2):

                                 With respect to the Revolving Loans:

                                 A rate equal to the "Prime Rate" in effect from
                                 time to time, plus 0.0% per annum.

                                 With respect to the Term Loan:

                                 A rate equal to the "Prime Rate" in effect from
                                 time to time, plus 0.25% per annum.

                                 With respect to all Loans:

                                 Interest shall be calculated on the basis of a
                                 360-day year for the actual number of days
                                 elapsed. "Prime Rate" means the rate announced
                                 from time to time by Silicon as its "prime
                                 rate;" it is a base rate upon which other rates
                                 charged by Silicon are based, and it is not
                                 necessarily the best rate available at Silicon.
                                 The interest rate applicable to the Obligations
                                 shall change on each date there is a change in
                                 the Prime Rate.

      7. MODIFIED COLLATERAL MONITORING FEE. The Collateral Monitoring Fee set
forth in Section 3 of the Schedule to Loan and Security Agreement is hereby
amended to read as follows:

         Collateral Monitoring

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

         Fee:                    [Omitted]

      8. MODIFIED UNUSED LINE FEE. The Unused Line Fee set forth in Section 3 of
the Schedule to the Loan Agreement is hereby amended to read as follows:

         Unused Line Fee:        In the event, in any calendar month (or portion
                                 thereof at the beginning and end of the term
                                 hereof), the average daily principal balance of
                                 the Loans and the aggregate amount of the
                                 Letters of Credit outstanding during the month
                                 is less than the amount of the Maximum Credit
                                 Limit, Borrower shall pay Silicon an unused
                                 line fee in an amount equal to 0.25% per annum
                                 on the difference between the amount of the
                                 Maximum Credit Limit and the average daily
                                 principal balance of the Loans and the
                                 aggregate amount of the Letters of Credit
                                 outstanding during the calendar month, which
                                 unused line fee shall be computed and paid
                                 monthly, in arrears, on the first day of the
                                 following month.

      9. MODIFIED MATURITY DATE. The Maturity Date set forth in Section 4 of the
Schedule to Loan and Security Agreement is hereby amended to read as follows:

         4. MATURITY DATE
            (Section 6.1):       MARCH 28, 2008.

                                 Notwithstanding the foregoing, with respect to
                                 the Term Loan: The outstanding principal
                                 balance of the Term Loan shall continue to be
                                 repaid by Borrower to Silicon in thirty-six
                                 (36) equal monthly payments of principal,
                                 having commenced on May 1, 2004 and continuing
                                 on the first day of each subsequent month until
                                 the earlier of the following dates: (i) April
                                 1, 2007, or (ii) the date the Term Loan has
                                 been indefeasibly paid in full, or (iii) the
                                 date the Revolving Loans are terminated, or
                                 (iv) the date this Agreement terminates by its
                                 terms or is terminated by either party in
                                 accordance with its terms. On the earlier to
                                 occur of the foregoing dates, the entire unpaid
                                 principal balance of the Term Loan, plus all
                                 accrued and unpaid interest thereon, shall be
                                 due and payable. Interest on the Term Loan
                                 shall be payable monthly as provided in Section
                                 1.2 of this Agreement.

      10. MODIFIED MINIMUM TANGIBLE NET WORTH FINANCIAL COVENANT. The Minimum
Tangible Net Worth Financial Covenant set forth in Section 5 of the Schedule to
Loan and

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

Security Agreement, entitled "5. FINANCIAL COVENANTS (Section 5.1)," is hereby
amended to read as follows:

          MINIMUM TANGIBLE
          NET WORTH:             Borrower shall, on a consolidated basis,
                                 maintain a Tangible Net Worth of not less than
                                 the following:

                                 For the month ending March 31, 2006 and each
                                 month ending thereafter: $5,000,000 plus an
                                 amount equal to (i) 50% of all consideration
                                 received after March 1, 2006 for equity
                                 securities and subordinated debt of the
                                 Borrower, plus (ii) 50% of the Borrower's net
                                 income in each fiscal quarter ending after
                                 March 1, 2006.

                                 Increases in the Minimum Tangible Net Worth
                                 Covenant based on consideration received for
                                 equity securities and subordinated debt of the
                                 Borrower shall be effective as of the end of
                                 the month in which such consideration is
                                 received, and shall continue effective
                                 thereafter. Increases in the Minimum Tangible
                                 Net Worth Covenant based on net income shall be
                                 effective on the last day of the fiscal quarter
                                 in which said net income is realized, and shall
                                 continue effective thereafter. In no event
                                 shall the Minimum Tangible Net Worth Covenant
                                 be decreased.

      11. MODIFIED DEFINITION OF ADJUSTED QUICK RATIO. The definition of
Adjusted Quick Ratio in Section 5 of the Schedule to Loan and Security Agreement
is hereby amended to read as follows:

          "Adjusted Quick Ratio" shall mean, as of any applicable date, the
          ratio of (i) consolidated cash, cash equivalents and Receivables of
          Borrower determined in accordance with generally accepted accounting
          principles, consistently applied, to (ii) Borrower's current
          liabilities plus the face amount of all outstanding Letters of Credit
          reserved against the Loans less Borrower's deferred revenues.

      12. MODIFIED REPORTING REQUIREMENTS.

          (a) As long as Borrower continually satisfies the Minimum Cash On Hand
Requirement (as defined above), Borrower shall be required, in addition to the
General Reporting Requirements described below, to submit monthly unaudited
financial statements and a Compliance Certificate as provided for in the Loan
Agreement.

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

          (b) If Borrower fails to comply with the Minimum Cash On Hand
Requirement, Borrower shall be required, in addition to the General Reporting
Requirement below, to submit monthly transaction reports, accounts receivable
agings, accounts payable agings, unaudited financial statements and a Compliance
Certificate as provided for in the Loan Agreement.

          (c) General Reporting Requirements. Borrower shall be required to
submit to Silicon annual operating budgets and projections, quarterly and annual
audited financial statements and such other reports and information as Silicon
may require from time to time as provided for in the Loan Agreement.

      13. STREAMLINE FACILITY AGREEMENT. Borrower and Silicon acknowledge that
that certain Streamline Facility Agreement between them dated March 30, 2005 is
no longer in effect.

      14. EXIM LOAN AGREEMENT. Reference is made to that certain Loan and
Security Agreement (Exim Program) dated May 5, 2003 between Borrower and Silicon
(the "Exim Loan Agreement"). Borrower and Silicon agree that no more loans will
be available under the Exim Loan Agreement. Moreover, once all Obligations under
the Exim Loan Agreement have been satisfied, the Exim Loan Agreement shall no
longer be in effect in accordance with the terms thereof.

      15. FEE. In consideration for Silicon entering into this Amendment,
Borrower shall pay Silicon a fee in the following amounts:

          (a) $40,000 (the "Year 1 Fee"), which is fully earned on a monthly
basis going forward and which shall be non-refundable and in addition to all
interest and other fees payable to Silicon under the Loan Documents. The Year 1
Fee shall accrue at the rate of $3,333.33 per month for each month (or partial
month) ending after the date hereof and shall be payable at the end of each
quarter. Silicon is authorized to charge said Year 1 Fee, as provided for above,
to Borrower's loan account.

          (b) $20,000 (the "Year 2 Fee"), which will be fully earned on a
monthly basis going forward, commencing with the first anniversary date of this
Amendment and which shall be non-refundable and in addition to all interest and
other fees payable to Silicon under the Loan Documents. The Year 2 Fee shall
accrue at the rate of $1,666.67 per month for each month (or partial month)
ending after the first anniversary date of this Amendment and shall be payable
at the end of each quarter. Silicon is authorized to charge said Year 2 Fee, as
provided for above, to Borrower's loan account.

      16. REPRESENTATIONS TRUE. Borrower represents and warrants to Silicon that
all representations and warranties set forth in the Loan Agreement, as amended
hereby, are true and correct.

      17. GENERAL PROVISIONS. This Amendment, the Loan Agreement, any prior
written amendments to the Loan Agreement signed by Silicon and Borrower, and the
other written documents and agreements between Silicon and Borrower set forth in
full all of the representations and agreements of the parties with respect to
the subject matter hereof and supersede all prior discussions, representations,
agreements and understandings between the

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         SILICON VALLEY BANK                         AMENDMENT TO LOAN AGREEMENT

parties with respect to the subject hereof. Except as herein expressly amended,
all of the terms and provisions of the Loan Agreement, and all other documents
and agreements between Silicon and Borrower shall continue in full force and
effect and the same are hereby ratified and confirmed.

   BORROWER:                           SILICON:

   ONYX SOFTWARE CORPORATION           SILICON VALLEY BANK

   BY  /s/ TERESA KOTWIS               BY /s/ BRIAN BOATMAN
       -----------------                  -----------------
         TREASURER                     TITLE RELATIONSHIP MANAGER

   BY  /s/  PAUL DAUBER
       ----------------
         SECRETARY OR ASS'T SECRETARY

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