I have a blackberry curve 8320 and nokia n800 an excellent combination for tethering. Both use 3.5 stereo voice jacks and are not compatible. Ordinary headphones will work in either.
The iphone compatible headset vmoda duo works fine with the blackberry but not with the n800.
I seem to experience difficulty with how each has wired the interrupt switch for call vs headphone. vmoda in n800 does not deliver stereo unless i press the switch on the microphone. n800 headset in the blackberry interfers with the music player by causing it to continuously pause.