I am not familiar with JBuilder8, but with remote debugging ;-)
suspend=y means, the vm won't start until a debugger is connected (that's why JBoss "hangs")
If JBuilder won't complain with something like "can't connect" or "connection refused" when starting the debug session, the connection is ok.
If breakpoints are ignored, be sure you are using the source files for the running binary. Better build JBoss out of the sources.
If this won't work: it is not a JBoss problem, try a JBuilder forum instead.