Exhibit 31.1


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

         I, SCOTT C. MCDONALD, certify that:
1.       I have reviewed this annual report on Form 10-K of Castelle;

2.       Based on my knowledge, this annual 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
         annual report;

3.       Based on my knowledge, the financial statements, and other
         financial information included in this annual 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 annual report;

4.       The registrant's other certifying officer(s) 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 annual 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(s) 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 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.



Date: March 29, 2004                          By:   /s/ SCOTT C. MCDONALD
                                                       Scott C. McDonald
                                           President and Chief Executive Officer


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