SAXParser throws SAXExceptions after many (serial) parses

[vogt@isxinc.com]

          Our WebSphere servlet application (re)uses SAXParsers from a
pool.
          We are sure that we are serializing the use of these.

          Sometimes, after thousands of reuses, we get miscelaneous
SAXExceptions and
          other Exceptions from parse().
          For Example:
          - FWK005 parse may not be called while parsing
          - org.xml.sax.SAXException: Stopping after fatal error: The
markup declarations contained or pointed to by the document type
declaration must be well-formed.
          - org.xml.sax.SAXException: Stopping after fatal error: A '('
character or an element type is required in the declaration of element type
"LocNm".  (Occurs for various elements)
          - ArrayIndexOutOfBoundsException: 0  (also with -2)


          We are using org.apache.xerces.parsers.SAXParser that was
included in the XSLT package
          on Alphaworks (or Lotus) but I don't know how to determine the
version.
          How do I determine the version?

          I looked for a "reset" method to try but don't see one.
          Is there a "reset", short of constructing a new one?

          I do set the content and error handler and a feature before each
parse.
          The XML to be parsed always uses the same dtd.

          Thanks for any help or suggestions,

          Michael Vogt   ISX Development