OK, now it all makes sense. When they set this 3300 up they used system speed calls to forward the extensions.

So the provider sends 4 digits, the PBX takes it and adds 75 in front, then there is a system speed call that takes 75xxxx and forwards to xxxx.

Wow, that was brutal....

Thank you all for your assistance, the thing that did it for me was checking the trunk service assignment to see that the 75 was being pumped in.

Regards