Yes based on the stack trace looks like the OpenSAML library does not like Java6 too much from a memory consumption standpoint. Especially during the phase where SAML xml needs to be produced from its Object model. I have no idea what the reason could be. I will have to check OpenSAML community. It may even turn out OpenSAML is not ready for Java6. I will have to do some digging to get to the root of it. Until then, use it on Java5. I recommend CR2 vs CR1 since there have been quite a bit of bug fixes and security enhancements with it. Thanks View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4194850#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...