Comment 80 for bug 221119

Just in order to test and for no better reason (my system with Intel i845 was working pretty well without Compiz), I decided to try the latest drivers by adding to my sources.list the following lines and upgrading:

deb http://ppa.launchpad.net/xorg-edgers/ubuntu intrepid main
deb-src http://ppa.launchpad.net/xorg-edgers/ubuntu intrepid main

Not a good idea, because when I booted up after the upgrade and arrived at the GDM screen, all I could see was a blank screen with faint Ubuntuish colours and no login text box, keyboard dead but mouse cursor visible. Keyboard not responding, I had to hard-reset the machine.

This is what I get in Xorg.0.log:

...
Backtrace:
0: /usr/X11R6/bin/X(xorg_backtrace+0x3b) [0x813164b]
1: /usr/X11R6/bin/X(mieqEnqueue+0x237) [0x8110ba7]
2: /usr/X11R6/bin/X(xf86PostMotionEventP+0xc2) [0x80d3ac2]
3: /usr/X11R6/bin/X(xf86PostMotionEvent+0x68) [0x80d3c28]
4: /usr/lib/xorg/modules/input//evdev_drv.so [0xaf7aff91]
5: /usr/X11R6/bin/X [0x80c9577]
6: /usr/X11R6/bin/X [0x80b246c]
7: [0xb8098400]
8: /usr/lib/libdrm.so.2(drmCommandWrite+0x3b) [0xb7b5be5b]
9: /usr/lib/xorg/modules/drivers//intel_drv.so(I830Sync+0xd5) [0xb7af2535]
10: /usr/lib/xorg/modules/drivers//intel_drv.so [0xb7b1ca3a]
11: /usr/lib/xorg/modules//libexa.so(exaWaitSync+0x65) [0xb7a1a195]
12: /usr/lib/xorg/modules//libexa.so(ExaDoPrepareAccess+0x7e) [0xb7a1b3be]
13: /usr/lib/xorg/modules//libexa.so [0xb7a200f2]
14: /usr/lib/xorg/modules//libexa.so [0xb7a20619]
15: /usr/lib/xorg/modules//libexa.so(exaDoMigration+0x64a) [0xb7a20dda]
16: /usr/lib/xorg/modules//libexa.so(exaCopyNtoN+0x3eb) [0xb7a1de3b]
17: /usr/lib/xorg/modules//libexa.so(exaComposite+0x856) [0xb7a23076]
18: /usr/X11R6/bin/X [0x8177ada]
19: /usr/X11R6/bin/X(CompositePicture+0x19a) [0x816056a]
20: /usr/lib/xorg/modules//libexa.so [0xb7a1e96d]
21: /usr/lib/xorg/modules//libexa.so(exaGlyphs+0x4f2) [0xb7a1f412]
22: /usr/X11R6/bin/X [0x8177da5]
23: /usr/X11R6/bin/X(CompositeGlyphs+0xa2) [0x815c9f2]
24: /usr/X11R6/bin/X [0x8169d5e]
25: /usr/X11R6/bin/X [0x8163155]
26: /usr/X11R6/bin/X(Dispatch+0x34f) [0x808c8ef]
27: /usr/X11R6/bin/X(main+0x47d) [0x8071d6d]
28: /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe5) [0xb7c9a685]
29: /usr/X11R6/bin/X [0x8071151]
ERROR: Server Lockup! Stuck in an infinite loop. See backtrace above.
ERROR: Server Lockup! Stuck in an infinite loop. See backtrace above.
...
[etc; the last line repeated hundreds of times.]

I know this might not be the best place to ask such a silly question, but how do I revert back to the working version of the Xorg drivers...?