VPN and Remote Desktop

I am trying to connect to my Windows XP Desktop in Office through VPN from my Windows XP Laptop. The remote desktop is enabled on my office desktop. The VPN connects fine and i am able to open my office intranet. But when i try to do remote desktop to the machine it says that Remote Desktop might not be enabled, which is not true.
I am able to remote desktop to a terminal server which is in my office but not to my desktop.
This was working fine earlier, but after my office laptop was reimaged , it stopped working.
Don’t know what’s going on. If i do a netstat -an, port # 3389 is listening.
Don’t know what can be the issue