Well, I had a lovely discussion with the Vodafone technical team who told me that the Vodafone network does not offer VoIP as part of their network. I asked why they had disabled internet telephony on my Nokia N95 and they said that they hadn't.
The salespeople told me that the phone was a standard Nokia N95 with all of the features of this phone.
I love it when they lie.
So, not sure when I can start to use VoIP - this is not over yet.