Hunting the Permgen classloader memory leak

In the past I have hunted several Memory leaks, but never a permgen leak. This is a totally different beast and there is considerably less literature and supportive tools than for heap leaks. Here some documents really worth reading:

http://frankkieviet.blogspot.se/2006/10/classloader-leaks-dreaded-permgen-space.html

http://frankkieviet.blogspot.it/2006/10/how-to-fix-dreaded-permgen-space.html

http://java.jiderhamn.se/2011/12/11/classloader-leaks-i-how-to-find-classloader-leaks-with-eclipse-memory-analyser-mat/#finding_the_leak

http://zeroturnaround.com/rebellabs/rjc201/

This one is a really awesome tutorial from the basics to the advanced: http://zeroturnaround.com/rebellabs/rebel-labs-tutorial-do-you-really-get-classloaders/

https://sites.google.com/site/eclipsebiz/The-Unknown-Generation-Perm