+1  A: 

I think that JBoss is started by bin\run.bat file (at least I see something like that in service.bat file).

In that case it should be sufficient to edit run.conf.bat file and change the -XX:MaxPermSize parameter. These parameter allows you to set up perm gen space size.

Lukasz Stelmach
Excellent. This worked for me.. Thank you very much.
Multiplexer