I am trying ssh forwarding over ssh. xterm is working fine but for
many programs, they appear in the process list on the remote machine
but I don't get the GUI. What can be the possible problem?

I am trying just for the heck of doing it but I prefer to have port
forwarding workarounds rather than X forwarding. I know there are
cases where X forwarding is to be done but otherwise for checking
intranet mail or using the remote
computer to browse works great with port forwarding.