When dragging, or holding the mouse down in general the mouse tends to 'let go'. In some situations the mouse grabs *through* the window. For example, I may be scrolling in okular and suddenly find myself dragging an item in the browser below. The behavior is independent of the application (it may fall through Dolphin onto Okular just as easily).

Highlighting text is the worst performing... It usually takes two to three goes to get the right range.

Is this a known issue? Known solution?

OS Information
OS: Linux x86_64
Current user:
System: openSUSE 11.3 (x86_64)
KDE: 4.5.3 (KDE 4.5.3) "release 8"
Display Info
Vendor: nVidia Corporation
Model: GeForce GTX 275
2D driver: nvidia
3D driver: NVIDIA 260.19.12
CPU Information
Processor (CPU): Intel(R) Core(TM) i7 CPU 920 @ 2.67GHz
Speed: 2,673.51 MHz
Cores: 4
Memory Information
Total memory (RAM): 11.8 GiB
Free memory: 8.3 GiB (+ 2.1 GiB Caches)
Free swap: 36.0 GiB