Dear All 

I had this exception being thrown, but only from our testing server. It was
fine in the development environment.

javax.servlet.ServletException : Cannot create bean of class blarblarBean   

I tried everything from checking the iplanet settings to recompiling the
classes, eventually resorting to stripping all the methods out of the bean
until it stopped throwing the error.

The problem was actually caused by a missing entry in a properties file
which was called by the bean. 

I hope this helps.