ntvdm hangs in fullscreen

[ReBeL]

Hello,
I recently reinstalled xp on my computer, with all the updates and service pack.
What I found out is that for some odd reason
the ntvdm.exe, the program that runs when you use old dos programs hangs if you switch it to full screen (some programs require full screen only, so it's a problem)
Example
I'll start command prompt,
and start debug
it will run ok
until I switch to full screen, then it hangs,
the program it self seems to work because I see the cursor flashing, but no keyboard/mouse input seems to affect it.
and when I switch back to window mode it still hangs
and I have no choice but to force it to shut.

Anyone ran in to this problem before?

Thanks