On one of the SRX51's I took the plunge and did a "do-release-upgrade -d" to Lucid from a fully working Karmic Xubuntu.
Starting without that xorg.conf in place, Xorg starts with 800x600 shifted to the top of the LCD but a VT switch away and back brings it to the centre of the LCD.
The custom xorg.conf that worked with Karmic (detailed in comment #12) causes Xorg to fail on Lucid with the same reports as bug #532579 "Segfault in libint10 when restarting xserver".
On one of the SRX51's I took the plunge and did a "do-release-upgrade -d" to Lucid from a fully working Karmic Xubuntu.
Starting without that xorg.conf in place, Xorg starts with 800x600 shifted to the top of the LCD but a VT switch away and back brings it to the centre of the LCD.
The custom xorg.conf that worked with Karmic (detailed in comment #12) causes Xorg to fail on Lucid with the same reports as bug #532579 "Segfault in libint10 when restarting xserver".