I am also affected by this bug, after an upgrade to kubuntu 11.04. Exactly the same situation. The situation occurs both with desktop effects switched on and off.
Laptop is lenovo thinkpad r500, video card is some Intel integrated device (Mobile 4 Series Chipset Integrated Graphics Controller). Charles, do you also have an Intel video card? Maybe there's something wrong with the graphics driver or something, since the situation occurs no matter which desktop environment we use...
I am also affected by this bug, after an upgrade to kubuntu 11.04. Exactly the same situation. The situation occurs both with desktop effects switched on and off.
Laptop is lenovo thinkpad r500, video card is some Intel integrated device (Mobile 4 Series Chipset Integrated Graphics Controller). Charles, do you also have an Intel video card? Maybe there's something wrong with the graphics driver or something, since the situation occurs no matter which desktop environment we use...
There is a bug report on exactly the same problem here: https:/ /bugs.launchpad .net/ubuntu/ +bug/774510, so these two bug reports probably should be merged.