Lock up When Spliting the window [ADDITIONAL INFO]

When I click on one of the splitting windows icons in the top right corner in a new project, the program becomes unavailable (Twirling circle meaning busy). And it doesn’t stop (left it for about an hour) until I Cntrl alt delete it into oblivion. I got no error messages.

It’s happened a few times.

System: Windows 7, 1.3 duo core, 6 gig ram, ATI Mobility Radeon 4550.

I have not been able to duplicate this with beta 1.3.

Which beta are you running?