The Sharp GX-30 has 'restricted' bluetooth which means it can only be used with a bluetooth headset. Although you can search for bluetooth devices, the GX-30 lacks any communication features such as serial port, object push and file transfer making the bluetooth feature useless unless you just want a headset.
The GX-32 resolved this issue with the bluetooth, however it is not posible to perform a software upgrade on the GX-30 because there are several hardware differences making it incompatible with the earlier model.
If you really need bluetooth your only option is to upgrade your phone, I owened the GX-30 for a while and I have yet to find a phone that has a screen which looks as good, the screen on my Samsung D600 looks poor compared to the GX-30's despite having the same resolution.