Please describe the problem:
At home I use a 19" monitor together with the builtin 15" display of my laptop. I use xrandr or the resolution preflet to switch the external monitor on and off. The external one is setup left next to the laptop. When it's there it seems to be "monitor 0", the laptop's display then is "monitor 1".
When I switch off the external display, the the internal becomes "monitor 0", which is good. However the panels that where on "monitor 1" before now are set to "monitor 0", which I can see in gconf-editor under /apps/panel/toplevels/[panel_name]/monitor. I think it would be better if the panel would stay on monitor 1 and would just be not shown, as long as the monitor is gone.

Steps to reproduce:
1. Connect a second monitor, left of the other one and activate it with xrandr (e.g. with `xrandr --output VGA --mode 1280x1024 --left-of LVDS`); it now becomes monitor 0, which is correct
2. Add a panel to the (presumably empty) right monitor
3. Use xrandr to disable the left monitor


Actual results:
The panels from the left ("primary") monitor AND the new panel from the right ("secondary") monitor get shown on the now only monitor. Sometimes (very rarely) one of them seems to be hidden under the other one, which I think is another bug.

Expected results:
Only the panels from the "primary" monitor should be shown on this. I.e. the gconf entry /apps/panel/toplevels/[panel_name]/monitor should not change, when I add or remove monitors.

Does this happen every time?
Yes

Other information: