crimson on tomcat 5

I've recently installed my web application on Tomcat 5, while before ran

on Tomcat 4.1. I've obtained this exception:

java.lang.IllegalStateException: can't declare any more prefixes in this
context
   at org.xml.sax.helpers.NamespaceSupport$Context.declarePrefix(Unknown
Source)
   at org.xml.sax.helpers.NamespaceSupport.declarePrefix(Unknown Source)
   at org.apache.crimson.parser.Parser2.processAttributeNS(Unknown Source)
   at org.apache.crimson.parser.Parser2.maybeElement(Unknown Source)
   at org.apache.crimson.parser.Parser2.parseInternal(Unknown Source)
   at org.apache.crimson.parser.Parser2.parse(Unknown Source)
   at org.apache.crimson.parser.XMLReaderImpl.parse(Unknown Source)
   at org.apache.xalan.processor.TransformerFactoryImpl.newTemplates(Unknown
Source)
   at org.apache.xalan.processor.TransformerFactoryImpl.newTransformer(Unknown
ource)

I've surfed on the internet searching the solution for this problem, but

at http://www.mail-archive.com/[email protected]/msg02769.html

says that crimson isn't compatible with newer version of sax included 
which in Tomcat 5.
Is this true?
If yes there is any new release of crimson in program?

thanks in advance,
Mirko Melis.