What kind of bluetooth device are you using on your Powerbook to connect with the Keyboard & Mouse?
If its USB make sure its plugged in correctly, also some USB bluetooth devices dont work too well if used in a USB hub, try it directly in your powerbooks USB port.
I pressume your keyboard & mouse have batteries to power them, try removing them for a few minutes than replace them.
Also read the "Read this before posting" in this section.
Hope this helps