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                                                                   EXHIBIT 31.1

                           CERTIFICATION PURSUANT TO
                                 SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

I, Kenneth J. Zuerblis, certify that:

     1.   I have reviewed this annual report on Form 10-K/A of Enzon
          Pharmaceuticals, Inc. ("Enzon");

     2.   Based on my knowledge, this report does not contain any untrue
          statement of a material fact or omit to state a material fact
          necessary to make the statements made, in light of the circumstances
          under which such statements were made, not misleading with respect
          to the period covered by this report;

     3.   Based on my knowledge, the financial statements, and other financial
          information included in this report, fairly present in all material
          respects the financial condition, results of operations and cash
          flows of the registrant as of, and for, the periods presented in
          this report;

     4.   The registrant's other certifying officer and I are responsible for
          establishing and maintaining disclosure controls and procedures (as
          defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the
          registrant and have:

          (a)  Designed such disclosure controls and procedures, or caused
               such disclosure controls and procedures to be designed under
               our supervision, to ensure that material information relating
               to the registrant, including its consolidated subsidiaries, is
               made known to us by others within those entities, particularly
               during the period in which this report is being prepared;

          (b)  Evaluated the effectiveness of the registrant's disclosure
               controls and procedures and presented in this report our
               conclusions about the effectiveness of the disclosure controls
               and procedures, as of the end of the period covered by this
               report based on such evaluation; and

          (c)  Disclosed in this report any change in the registrant's
               internal control over financial reporting that occurred during
               the registrant's most recent fiscal quarter (the registrant's
               fourth fiscal quarter in the case of an annual report) that has
               materially affected, or is reasonably likely to materially
               affect, the registrant's internal control over financial
               reporting; and

     5.   The registrant's other certifying officer and I have disclosed,
          based on our most recent evaluation of internal control over
          financial reporting, to the registrant's auditors and the audit
          committee of the registrant's board of directors (or persons
          performing the equivalent functions):

          (a)  All significant deficiencies and material weaknesses in the
               design or operation of internal control over financial
               reporting which are reasonably likely to adversely affect the
               registrant's ability to record, process, summarize and report
               financial information; and

          (b)  Any fraud, whether or not material, that involves management or
               other employees who have a significant role in the registrant's
               internal control over financial reporting.

November 10, 2004

                                /s/ Kenneth J. Zuerblis
                                ------------------------------------------------
                                Executive Vice President Finance,
                                Chief Financial Officer and
                                Corporate Secretary
                                (Principal Financial Officer and
                                Acting Principal Executive Officer)


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