Forward a perticular extension to another extension

General Help
1

Hi,
I was wondering if its at all possible to force an extension to forward to another extension (all internal). So for example if the extension in question was 123 I always want calls coming from 123 to 456 to go to 789 (or am I over complicating things?)
Thanks

2

So you want calls originating from extension 123, no matter what extension was called, to always terminate on extension 789?

3

That was the case but Im going down a different route now. The reason for this was a for a speaker phone to dial a particular number. Im now trying to reconfigure the speaker so it dials a different number (the number I was after) but I have managed to ban it - so I guess my next question is how do I remove an IP from a black list intrusion detection?

Thanks