VoIP calls (both SIP and Skype) do go through two Bluetooth headsets which support HFP and HSP profiles.

My car built-in Bluetooth however, supports HFP and OPP profiles only. So, if calls come into my SIM card in N900, car Bluetooth picks up the ring using HandsFreeProfile (HFP) I suppose. But if the call comes into my VoIP accounts (both SIP and Skype) on N900, the car Bluetooth will not recognize the incoming call.

Is this because VoIP calls use HeadSetProfile (HSP) and not HandsFreeProfile (HFP)? Is there anything I can do to remedy this by sending VoIP calls using HFP just like SIM calls?

Many thanks in advance.