Please describe the problem:
[pasted from launchpad bug report]

I have the panel with the Window List setup with the following settings: orientation left, 200 pixels, expand on. I have three monitors using xinerama.

This appears to occur after having more than 8 windows open, since when I close windows it stops occurring after I have 8 windows left.

The window buttons will resize/regroup so that I cannot hit them. If they are shown in a single column, then when I click Each time that I try to click one of the windows in the list it will display the list in two columns on mouse down, and go back to one column on mouse up. If I keep the mouse down, it will keep switching the list between one and two columns. It will randomly end up being one or two columns of list.

This is incredibly annoying, particularly given that I have three widescreen monitors attached and it doesn't really make sense to put the panel along the bottom for me.

Ubuntu 9.04
gnome-panel 2.26.0-0ubuntu7

Steps to reproduce:
1. Align the panel to the left, place the window list in that panel
2. Open more than 8 windows
3. Try to click a window title in the panel, notice how you cannot because it keeps switching


Actual results:
The panel switches between displaying one and two columns of titles. 

Expected results:
I would expect a window to be raised

Does this happen every time?
As far as I can see, on my system it does. 

Other information:
Originally reported on launchpad: https://bugs.launchpad.net/ubuntu/+source/gnome-panel/+bug/407876