problems with remote X display

[sagar]

Hi people I am newbie to linux. I setup Mandrake 8.0 on my system recently. I use a vpn client to connect to my work place. The VPN works fine. I can ping the other machines, rsh, telnet and ftp to them. The problem arises when I try to display remote X. Whenever I telnet or rsh and check the DISPLAY variable, it is correctly set to mymachine:0, However when I type xterm or something , the whole machine freezes and I have to pull the plug. Can anyone let me know why this is happening? Note that Every other form of communication is possible with the remote machine. I even use VNC and it works fine. Its just the remote X display that doesnt work.
Thanks in advance