The SAAJ RI tries to Pool SAXParser instances for efficiency. But it appears
that class com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl
adds all the symbols to the Xerces SymbolTable associated with the SAXParser.
Since the SymbolTable is never reset or cleared, over time as we parse new types
of messages (or even the same message, with different namespaces used), over
time the SymbolTable will fill up.
We tried calling reset() on the parser before returning to the pool but that
does not apparently clear the SymbolTable.
I will create a Testcase that shows the problem soon.
Please see the related issue where the User has stated more details :