Hi, got my 1st ever iMac to play with (after years of being with PC's)

It's only a iMac G3, but I'm well impressed.
Even managed to install OS X Tiger, which runs quite nice.

Anyway, not to bore you with a long story, and get to the point:

I have a D-Link DBT-120 Bluetooth USB Dongle (works fine on the PC)

But does not seem to be working on the iMac

The Mac see's it and allows me to turn on bluetooth and also change settings, but when I fire up my PDA with bluetooth on. There is just no communication, nothing is ever found.

Just wondering, may there be any obvious things I'm missing?

Thanks.

Oh yes, I have the Bluetooth dongle plugged into the left hand side port on the keyboard in case that makes any difference?