Comment 29 for bug 532174

@Thag:

You are into something completely different. This bug just handles the registration of the sun-java plugin.

Looking at the stacktrace you provided I see that you are already using the plugin. But on your side something prevents it from remotely loading classes on demand:
Caused by: java.net.ConnectException: Connection timed out

So do you already checked your firewall rules or e.g. your proxy/nat/routing? Looks like something in between just drops the packets that the plugin sends.