Vista - Remote Desktop automatically logs user out

Hey folks!

For some reason, when I close the remote desktop window (not log out, I mean close as in click the X button in the top right corner) it seems to be logging the user out anyway, even though the message says otherwise.

I want my main machine, running Vista Ultimate (x32) stays logged in all day. I walk around the office to meetings and such with a netbook running XP. In the meetings, I log into my main machine via Remote Desktop (the default windows client that comes with XP Home (x32)). I continue to work in the meeting or look things up. After the meeting, I close the lid on my netbook putting it in standbye, whereby the RDC session ends. Or, I close the RDC session without logging out. When I do, I get the message that "This will disconnect your Terminal Services session. Your programs will continue to run while you are disconnected. You can reconnect to the session later by logging on again.".

The problem is, when I get back to my main machine and log in, I find I have been logged out and am starting from a fresh login -- all my apps closed and anything I was working on that I didn't save is lost(!).

Remote Desktop is not supposed to be logging me out. I don't select log out from the remote machine, I either close the netbook or close the RDC session. I am even told it's not going to log me out and my apps will still be runing. Yet, it does log me out.

Is this a setting in Vista that auto-logs out when an RDC session ends? What can I do to prevent this auto-logout whenever I end a remote desktop session?

Thanks!