Loftus: My Android (JB4.2) smartphone supports one SIM-based account and several VOIP accounts. My VOIP provider has assigned a (landline) number to the VOIP account - hence, 1 phone with two numbers.
I wonder if you could find a VOIP provider that would port one of the 021 numbers...
I know of none. 2talk have Non-Geographic (028) number ranges, but AFAIK, no SMS Interconnects and probably other requirements to terminate calls from such numbers.
