Best way round duplicate sim problem for built in car phone?

I have just got a car with built in GMS Telephone. This requires a sim card in the car to work it.O2 do not do duplicate sims(or wont). Another way is having a second sim card, with another number and diverting calls. This is however expensive.This is a business line so i cannot change networks. Help


Dave|||Without changing network I do not know a way of doing this. However to be perfectly honest personally I would opt for a good in car bluetooth kit professionally installed and use that with your existing handset.