Problems with 8.10 VGA output for GDM and guest account

[Samuel Rohde]

Ever since I upgraded to Ubuntu 8.10 I am not able to see the GDM screen and the guest account on my 32" TV/Monitor. The only way for me to see them is when I switch screens to a 17" screen. I am the administrator for the computer and I am able to see my account normally, just not the guest account and the GDM theme. There is only my account and a guest account on my computer. How can I fix this problem?