8-K

                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549

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                                    FORM 8K
                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934


Date of report (Date of earliest event reported)   May 3, 2000
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                              QUINTUS CORPORATION
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               (Exact name of Registrant as Specified in Charter)


              Delaware                                          77-0021612
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    (State or Other Jurisdiction     (Commission File         (IRS Employer
          of Incorporation)              Number)           Identification No.)


47212 MISSION FALLS COURT, FREMONT, CALIFORNIA                        94539
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(Address of Principal Executive Offices)                             (Zip Code)


Registrant's telephone number, including area code        (510) 624-2800
                                                 -------------------------------

                                      N/A
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         (Former Name or Former Address, if Changed Since Last Report)





Item 5.  Other Events.

     On May 3,2000, the Registrant filed a prospectus supplement under Rule
424(b)(3) of the Securities Act of 1933, as amended, to the proxy
statement/prospectus dated April 11, 2000 relating to the proposed merger of
Mustang.com, Inc. into a subsidiary of the Registrant.

     A copy of the supplement to the proxy statement/prospectus is attached
hereto as Exhibit 99.1.


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                                   SIGNATURE

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                            QUINTUS CORPORATION


                                            By: /s/ Susan Salvesen
                                               --------------------------------
                                               Name:  Susan Salvesen
                                               Title: Chief Financial Officer
May 3,2000


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EX-99.1

                                                                   EXHIBIT 99.1


SUPPLEMENT TO PROXY STATEMENT                           PROSPECTUS SUPPLEMENT
             OF                                                  OF
      MUSTANG.COM, INC.                                  QUINTUS CORPORATION


     The proxy statement/prospectus dated April 11, 2000 relating to a proposed
transaction pursuant to which a subsidiary of Quintus Corporation will merge
with Mustang.com, Inc. is hereby supplemented to include the following
information:

     On April 19, 2000, Quintus announced its revenues for the fourth fiscal
quarter and fiscal year ended March 31, 2000. Revenues for the quarter were
$16.1 million, a 90% increase over revenues of $8.5 million in the fourth
quarter of fiscal year 1999. On a pro forma basis, excluding the impact of
acquisition- related charges and the amortization of deferred stock
compensation and adjusting for the inclusion of preferred shares prior to their
conversion to common stock, net loss from continuing operations for the quarter
was $2.0 million or $(.06) per share, compared to $172,000 or $(.01) per share,
for the same period in fiscal 1999.

     For fiscal year 2000, Quintus' revenues were $51.7 million compared to
$30.3 million for the same period last year, an increase of 71%. Excluding the
impact of acquisition-related charges and the amortization of deferred stock
compensation and adjusting for the inclusion of preferred shares prior to their
conversion to common stock, net loss from continuing operations for the year
was $4.6 million or $(.18) per share, compared to $7.2 million or $(.38) per
share, for the same period in fiscal 1999.

     For the fourth fiscal quarter, including acquisition-related charges and
the amortization of deferred stock compensation, Quintus' net loss from
continuing operations for the quarter was $5.4 million, or $(.17) per share,
compared to a net loss of $1.0 million or $(.31) per share for the same period
last year. For the year ended March 31, 2000 on the same basis, net loss from
continuing operations was $15.9 million or $(1.10) per share, compared to $10.6
million or $(3.73) per share for the same period in fiscal 1999.

     Quintus also recently announced the appointment of Paul Bartlett as its
Chief Operating Officer and the appointment of Nancy Brumfield as its Chief
Marketing Officer. Mr. Bartlett will be responsible for Quintus' worldwide
sales, customer services and engineering activities. Ms. Brumfield will be
responsible for defining and implementing Quintus' marketing strategy. Quintus
also


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announced that John Burke, President, has left the company effective April 17,
2000.

     On April 19, 2000, Mustang.com, Inc. announced its results for its first
quarter ended March 31, 2000. Mustang.com announced that its revenues had
increased 82% to $1,409,988 from $772,982 reported for the prior year period.
The net loss for the quarter was $244,525, or $(.04) per basic and diluted
share, as compared to the net income of $10,299, or $(.00) per basic and
diluted share, reported a year ago.

     The date of this proxy statement/prospectus supplement is May 3, 2000.


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