Version:           2.3.2 (using KDE 4.5.1) 
OS:                Linux

I have an English UK keyboard and the global hotkeys for increase/decrease volume are set to "Meta++" and "Meta+-". These work if I press the "-" next to the letters, but not the numpad one. On the hotkey selection menu, attempting to select the numpad "-" will simply throw the hotkey selection from "Custom" back into "Default".
In my keyboard, the "+" symbol has to be accessed with "Shift+=" which when I try it, the music scrolls backwards.

Reproducible: Always

Steps to Reproduce:
Select "Configure hotkeys" from the options menu.
Locate "Decrease Volume".
Select "Custom"
Press "Meta+-" (numpad -)

Actual Results:  
The selection jumps back to "Default"

Expected Results:  
Custom hotkey becomes "Meta+(numpad-)" (or similar)