Have you tried running any thread dumps to see "what's hot"?
Have you tried removing parts of the configuration to see which component is the culprit (i.e. is it a GF resource, something your app(s) does on load, etc.)
Kind of hard to say with the limited info you've given us.
[Message sent by forum member 'whartung' (whartung)]
http://forums.java.net/jive/thread.jspa?messageID=248924