I'm seeing exactly these symptoms with xserver-xorg-video-vesa 1:1.3.0-1 for i386
>From my /var/log/syslog: Jul 25 23:36:12 Valiant gdm[3392]: Xinerama active, but <= 0 screens? Jul 25 23:36:32 Valiant gdm[3384]: gdm_child_action: Aborting display :0 -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]