Classloading issues / SAXParserFactory

hi, I keep getting the following error as I execute and action (login button) of my plugin:

java.lang.ClassCastException: org.apache.xerces.jaxp.SAXParserFactoryImpl cannot be cast to javax.xml.parsers.


from what I've read, a plugin get it's own classloader, and that loads the classes from the plugins lib directory? I've tried various combinations of  adding all the libs I need into this dir,  removing jars from the IJSD,  adding :-Djavax.xml.parsers.SAXParserFactory=org.apache.xerces.jaxp.SAXParserFactoryImpl to the VM args - all in vain, I keep running  into class loading / implementation issues. I am confused about the following:

Do the plugin /lib jars get loaded with by plugin?
Can I remove jars that clash from the IJ-SDK?
Should I export all dependencies?
Do I need entreies for Compile & Runtime dependencies?

Sorry if some of these sound dumb, I've been at this for towo night and I aint getting much code down ;-)


Any pointers much appreciated, I've tried anything that seemed relevant in fourm.

Thanks,
Alan