Bluetooth mouse problems

I don't know if this belongs in the OS X forum, or some other area.. But the problem is on my G4 Mini. I have internal BlueTooth, and a Kensington bluetooth mouse.. When the system is idle for a long period of time (say overnight) the mouse does not work anymore. I press the discover button on the mouse and it still just won't work. And I can't seem to navigate ANYWHERE in OS X without a mouse.. I feel like a man with no arm and legs.. heh.. Is there some kind of hotkey to tell OS X to go into discovery mode to find the mouse that's also in discovery mode?
The keyboard (also bluetooth) is very reliable and never seems to disconnect. For now I'm just using my Microsoft wireless USB mouse..
Thanks for the help.

Nobody knows...

I'm using bluetooth on a mini but with an apple mouse. Under your bluetooth settings is it checked to enable devices to wake computer? Other than that I don't know because I haven't used a kensington.