Comment 32 for bug 661450

I am running Ubuntu 11.04 and only had problems with multiple monitors with Unity (as I have already displayed above).
No problems with classic desktop (gnome panel) and now for 2-3 weeks I am running Gnome3 Shell, no problems at all!
Before switching to Gnome Shell, Unity behaviour was a bit buggy, sometimes not working at all (like mentioned) and sometimes I had to redo the change of monitor configuration several times until it worked.
For example:
1. plug second monitor to laptop
2. unity shows buggy placement of tray on the monitor
3. switch of second monitor from Monitors applet
4. switch on mirroring
5. switch off mirroring
6. switch on extend to screen
7. switch off extend to screen
...
Repeat 4-7 several times until it finally worked. Until the next reboot.