Comment 40 for bug 292214

Are you sure you installed 1.9.100 in /usr/lib/xorg/modules/drivers/mga_drv.so (the driver installs to another directory by default)? And I think I also manually applied any relevant patches from the 1.4.9 Ubuntu package before building the driver, but I don't remember if that included anything important.

I should also note that Metacity is only useable under 1.9.100 if I enable compositing (/apps/metacity/general/compositing_manager gconf key).

See also this xorg bug that prevents 1.9.100 to be used with Jaunty's xorg: http://bugs.freedesktop.org/show_bug.cgi?id=20380

There are still some annoyances in my setup with 1.9.100, e.g. none of the video outputs seem to work ok. But xrandr with dual screen and compositing work.