When using multiple user accounts simultaneously (user + admin account) the entire OS freezes or the UI becomes unavailable for both user accounts and I'm forced to ctrl+alt+f1 and sudo shutdown -r Now

Hello,

I'm having a problem with the X locking up/showing a black screen. This started in edge eft (ubuntu 6.10). Here is the repro sequence

1) Create 2 accounts 1 user account and 1 admin account
2) start ubuntu
3) at the login screen log on to the user account with limited privs
4) Then using the ui Applications->System Tools -> New login (basically invoke new login)
5) login as the admin user
6) switch to the user account using ctrl+alt+f7 (you'll be prompted to enter the password since the screen gets locked)
7) play a movie or perform some other operation in the user account.
8) while the movie is playing switch back to the admin account using ctrl+alt+f8 or ctrl+alt+f9.
9) repeat steps 6 to 8, you'll see that eventually ctrl+alt+f8 and ctrl+alt+f9 will show a black screen for both the user and the admin accounts or the entire OS will freeze.

Note this seemed to have started in 6.10 and is still a problem, even in 7.04