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EXHIBIT 4.3 - AMENDMENT NO. 1 TO PREFERRED SHARES RIGHTS AGREEMENT


              AMENDMENT NO. 1 TO PREFERRED SHARES RIGHTS AGREEMENT

         Amendment No. 1 (the "AMENDMENT"), dated as of February 20, 2001, to
the Preferred Shares Rights Agreement (the "RIGHTS AGREEMENT"), dated as of
August 5, 1998, between New Era of Networks, Inc., a Delaware corporation (the
"COMPANY"), and BankBoston, N.A., is being executed at the direction of the
Company.

         WHEREAS, BankBoston, N.A. has resigned as Rights Agent under the Rights
Agreement;

         WHEREAS, on February 8, 2001, the officers of the Company appointed
American Stock Transfer & Trust Company as the new Rights Agent under the Rights
Agreement;

         WHEREAS, on February 8, 2001, the officers of the Company decreased the
capital requirement for a Rights Agent appointed under Section 21 of the Rights
Agreement from $50 million to $10 million;

         WHEREAS, the Company, Sybase, Inc., a Delaware corporation ("PARENT"),
and a Delaware corporation and wholly owned subsidiary of Parent ("MERGER SUB"),
intend to enter into an Agreement and Plan of Reorganization (the "MERGER
AGREEMENT") pursuant to which, among other things, Merger Sub will commence an
exchange offer for shares of common stock of the Company (the "OFFER") and
thereafter Merger Sub will merge with the Company (the "MERGER") and each
remaining share of common stock of the Company will be converted into the right
to receive shares of common stock of Parent, upon the terms and subject to the
conditions of the Merger Agreement;

         WHEREAS, on February 19, 2001, the Board of Directors of the Company
resolved to amend the Rights Agreement to render the Rights inapplicable to the
Offer, the Merger and the other transactions contemplated by the Merger
Agreement; and

         WHEREAS, Section 27 of the Rights Agreement permits the Company from
time to time to supplement and amend the Rights Agreement.

         NOW, THEREFORE, in consideration of the foregoing and the agreements,
provisions and covenants herein contained, the parties agree as follows:

         1.       Section 1(q) of the Rights Agreement is hereby amended to read
                  in its entirety as follows:

         "EXPIRATION DATE" shall mean the earliest to occur of: (i) the Close of
Business on the Final Expiration Date, (ii) the Redemption Date, (iii) the time
at which the Board of Directors orders the exchange of the Rights as provided in
Section 24 hereof, or (iv) immediately prior to the acceptance for payment of
shares of common stock in the Offer (as such term is hereinafter defined).

         2.       Section 1(cc) of the Rights Agreement is hereby amended to
                  read in its entirety as follows:

         "RIGHTS AGENT" shall mean American Stock Transfer & Trust Company or
its successor or replacement as provided in Sections 19 and 21 hereof.

         3.       Section 1 of the Rights Agreement is hereby amended by adding
                  the following new paragraph at the end of Section 1:

         "Notwithstanding anything in this Agreement that might otherwise be
deemed to the contrary, neither Sybase, Inc. ("PARENT") nor any of its
Affiliates or Associates shall be deemed an Acquiring Person and none of the
Distribution Date, Transaction or Triggering Event shall be deemed to occur, in
each such case, by the approval, execution, delivery or performance of the
Agreement and Plan of Reorganization dated as of February 20, 2001, including
any amendment or supplement thereto (the "MERGER AGREEMENT") among Parent, a
wholly owned subsidiary of Parent and the Company, the announcement,
commencement or consummation of the Offer or the Merger (as defined in the
Merger Agreement) or the



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consummation of the other transactions contemplated by the Merger Agreement,
including the execution of the Company Stockholder Agreements (and the
irrevocable proxies attached thereto), dated as of February 20, 2001 between
Parent and certain stockholders of the Company. No such event shall entitle or
permit the holders of the Rights to exercise the Rights or otherwise affect the
rights of the holders of Rights, including giving the holders of the Rights the
right to acquire securities of any party to the Merger Agreement."

         4.       Section 21 of the Rights Agreement is hereby amended to read
                  in its entirety as follows:

         "Section 1. Change of Rights Agent. The Rights Agent or any successor
Rights Agent may resign and be discharged from its duties under this Agreement
upon thirty (30) days' notice in writing mailed to the Company and to each
transfer agent of the Preferred Shares and the Common Shares by registered or
certified mail, and to the holders of the Rights Certificates by first-class
mail. The Company may remove the Rights Agent or any successor Rights Agent upon
thirty (30) days' notice in writing, mailed to the Rights Agent or successor
Rights Agent, as the case may be, and to each transfer agent of the Preferred
Shares and the Common Shares by registered or certified mail, and to the holders
of the Rights Certificates by first-class mail. If the Rights Agent shall resign
or be removed or shall otherwise become incapable of acting, the Company shall
appoint a successor to the Rights Agent. If the Company shall fail to make such
appointment within a period of thirty (30) days after giving notice of such
removal or after it has been notified in writing of such resignation or
incapacity by the resigning or incapacitated Rights Agent or by the holder of a
Rights Certificate (who shall, with such notice, submit his or her Rights
Certificate for inspection by the Company), then the registered holder of any
Rights Certificate may apply to any court of competent jurisdiction for the
appointment of a new Rights Agent. Any successor Rights Agent, whether appointed
by the Company or by such a court, shall be a corporation organized and doing
business under the laws of the United States or of any state of the United
States, in good standing, which is authorized under such laws to exercise
corporate trust or stockholder services powers and is subject to supervision or
examination by federal or state authority and which has at the time of its
appointment as Rights Agent a combined capital and surplus of at least $10
million. After appointment, the successor Rights Agent shall be vested with the
same powers, rights, duties and responsibilities as if it had been originally
named as Rights Agent without further act or deed; but the predecessor Rights
Agent shall deliver and transfer to the successor Rights Agent any property at
the time held by it hereunder, and execute and deliver any further assurance,
conveyance, act or deed necessary for the purpose. Not later than the effective
date of any such appointment, the Company shall file notice thereof in writing
with the predecessor Rights Agent and each transfer agent of the Preferred
Shares and the Common Shares, and mail a notice thereof in writing to the
registered holders of the Rights Certificates. Failure to give any notice
provided for in this Section 21, however, or any defect therein, shall not
affect the legality or validity of the resignation or removal of the Rights
Agent or the appointment of the successor Rights Agent, as the case may be.

         5. The Rights Agreement shall not otherwise be supplemented or amended
by virtue of this Amendment, but shall remain in full force and effect. This
Amendment may be executed in one or more counterparts, all of which shall be
considered one and the same amendment and each of which shall be deemed an
original.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and attested, all as of the day and year first above written.

NEW ERA OF NETWORKS, INC.                    AMERICAN STOCK TRANSFER &
                                             TRUST COMPANY as Rights Agent

By: /s/ Leonard M. Goldstein                 By: /s/ Herbert J. Lemmer
   -----------------------------------          -------------------------------

Name:    Leonard M. Goldstein                Name:    Herbert J. Lemmer
      --------------------------------            -----------------------------

Title:  Senior Vice President, Senior        Title:   Vice President
      --------------------------------             ----------------------------
Counsel and Secretary



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