Originally Posted by m419:
“Well when I had a BT caller display unit on a Telewest line it said 'Unavailable' when people called from abroad or from certain UK networks. When you dial 1471 from a Telewest phone it will say something like 'Sorry the last call was from a network that it is unable to transmit numbers'”
True cable CLID is a bit hit and miss, I think they do only use unavailable when from a abroad, BT will flag international. Just a shame Telewest can never do anything properly, yes they were the first in the UK to give the time and date with the number on 1471 when BT were only giving the number, they have good ideas Telewest but poorly implement them.
Anyway none of that is a problem for me VoIP has none of this hiding International numbers, it just displays them.
As the OP was on BT they will get International flagged up on international calls, and unavailable on calls from within the UK that can't/don't transmit numbers.