DWP

I have been searching for an application that does the following (which is how I came across DWP): Based on a regexp-type digit match, decide which application to use to make a caller (eg normal cal or VOIP) I would set it to say: (I am in the UK) If it started with a + or 00 but not +44, then use a...

Ah - thanks. That's not very obvious is it?

I must be being thick, but I cannot for the life of me find any place to set VOIP accounts nor to call anyone using VOIP. Can anyone help?