Seeking SAXException pattern

[Tim Bray <tbray@textuality.com>]

I'm writing some java code that uses a basic SAX parser, and I haven't 
done this for years if ever, and the callback routines all have 
signatures that throw SAXExceptions, e.g.

   public void characters(char [] s, int start, int length)
     throws SAXException

So, suppose I'm in this callback and something horrible happens; for 
example I discover that the content that I'm looking at here is 
completely bogus.  I can't throw an Exception of any kind without 
screwing up the signature.  So I have this pattern all over my code.

   try
   {
     myValidationCode(s, start, length);
   }
   catch (Exception e)
   {
     throw new SAXException(e);
   }

And then I have to catch the SAXException and pick it apart to see if 
it's really one of mine.  All of which seems kind of dorky.  I'm sure 
there must be a standard good practice that's been developed here?  
-Tim