I'm not sure about in the PC, but you can unplug the headset from the live adapter, and use the headset on your cell phone, I kinda look silly walking around with it, but it's worked for me.
Where as the cell phone (and live headset) plug is 2.5mm, the ones for the pc, and standard headphones, are 3.5mm.
If you do manage to find a convertor for the pc, it'll probably be 2 wires, one for the mic, and one for the headset (unless it's one, then it'll probably be only the mic, and you'll have to find some headphones).