I solved the issue with the analogue phone lines by getting rid of them. For the princely sum of 5.95 per month, Sipgate offer a trunking service, which means you can get your Virgin Media provided phone number transferred to them, and they will forward all calls to that number back to your own Asterisk system.
I've not done anything too complex so far, but it all works. If someone calls, then the VoIP phones (the Cisco ones) ring - first the main ones, then if they aren't answered the ones in the office and craft room get added on, and then if they are not answered, the mobiles ring!
If the call drops through to voicemail, the message is sent via an email attachment to us, so we can pick it up on our mobiles wherever we are as well.
Now Virgin Media charged me 17.95 a month for the privilege of a phone line. Since I don't need that any more, I wonder what their reaction will be when I ask that I have that money taken off my bill? (Please note this only works if your current provider doesn't
use the phone line to provide your broadband. Obvious when you think
All bets taken. Mine is that I might get a discount of a fiver after months of haggling.
*** Wrong again. After haggling, VM tell me that it is actually more expensive to change package to stop paying the line rental than it is to keep it. We need a bit more OFCOM legislation I feel.