Use a T-616 as just a bluetooth handset?

I've an old Sony Ericsson T-616 I'm no longer using. Can I use it as a
bluetooth handset for things like Skype or VoIP (via asterisk). Do I need a
SIM card in it and, if so, would a pay-as-you-go card that never got used
for outbound cards work (and stay working)?

Thanks,
-Bill Kearney