Hi Karthik,
Stop Jboss first.
Go into your Jboss folder and clear out the log:
cd /opt/jboss-4.2.3.GA/server/default/log/ or C:\jboss-4.2.3.GA\server\default\log\
Rename the server.log currently in there.
Start Jboss next and reproduce the problem, load up Enterprise Management.
After that's done, please send us your server.log.
We can also see that you have an issue opened, 00083771 // Unable to start CA Enter mgr - please upload your logs there so we can see the exact errors you're receiving within your log.
Thanks,
Eric