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                                                                     EXHIBIT 3.7


                            CERTIFICATE OF AMENDMENT
                                       TO
                          CERTIFICATE OF INCORPOARTION
                                       OF
                             CELERITY SYSTEMS, INC.,
                             A DELAWARE CORPOARTION

         The  undersigned,  in order to amend its Certificate of  Incorporation,
hereby certifies as follows:

         FIRST:  The name of the Corporation is Celerity Systems, Inc.,

         SECOND:  The Corporation hereby amends its Certificate of Incorporation
as follows:

         Effective as of the close of business on April 19, 2002 (the "Effective
Time"),  each twenty (20) issued and outstanding shares of Common Stock shall be
combined  into one (1)  validity  issued and  outstanding  share of Common Stock
("the Reverse Stock Split"). The par value of Common Stock shall not be affected
by the Reverse Stock Split.  Each stock  certificate that prior to the Effective
Time  represented  shares of Common Stock shall,  following the Effective  Time,
represent the number of shares into which the shares of Common Stock represented
by such  certificate  shall have been  combined.  This  conversion  shall  occur
automatically  and  without  any  action on the part of the  shareholders.  Each
fractional  share shall be rounded up to next whole share. No fractional  shares
or scrip shall be issued by reason of this  Amendment,  nor shall any fractional
shares or scrip be issuable in respect of any options,  warrants or other rights
of any nature heretofore existing to acquire shares of Common Stock. Each holder
of a certificate or certificates (the "Old  Certificates,"  whether one or more)
shall be entitled to receive  upon  surrender  of such Old  Certificates  to the
Company's  transfer agent for  cancellation,  a certificate or certificates (the
"New  Certificates,"  whether one or more) responding the number of whole shares
of the new Common Stock into which and for which the shares of old Common Stock,
formerly  represented by the Old  Certificates so surrendered,  are reclassified
under the terms of the Reverse Stock Split.

         THIRD:  After  taking into account the Reverse  Stock Split,  the first
sentence of Paragraph FOURTH of the Certificate of  Incorporation  pertaining to
the authorized stock of the Corporation is hereby amended to read as follows:

         The total number of shares of capital stock which the  Corporation  has
authority to issue is (i) Two Hundred and Fifty Million  (250,000,000) shares of
Common Stock with a par value of $0.001 ("Common  Stock") and (ii) Three Million
(3,000,000)  shares of Preferred  Stock with a par value of $0.01 per share (the
"Designation Preferred Stock").

         The amendment effected herein was authorized by the affirmative vote of
a  majority  of (i) the  Board of  Directors  and (ii)  the  outstanding  shares
entitled to vote thereon at the Corporation's annual shareholders'  meeting held
on April 9, 2002.

         IN  WITNESS  WHEREOF,  I  hereunto  sign my name  and  affirm  that the
statements made herein are true under the penalties of perjury, this 17th day of
April, 2002.


                                           /s/ Kenneth D. Van Meter
                                           -------------------------------------
                                           Kenneth D. Van Meter
                                           President and Chief Executive Officer