Telco Diversion

Hello again to all.
We have a client who is running a new install of FreePBX 3.21.63-8 and have asked me a question that has bugged them through and all flavors of asterisk distros they have used.
We are in West Australia and the Client has a branch in Port Hedland. This area is frequently troubled by cyclones and the phones and power often go out during these times.
They are using BRI (Basic Rate ISDN) through an Epygi Gateway and want to be able to dial the Telco’s diversion codes to send all calls to Perth branch before a cyclone hits. Telstra charge them $200 a pop to divert from the exchange (and i think again to undivert)
What they need to send is: *21#
To undivert is: #21#
From what i gather, asterisk “eats” the # symbol as the send key and the call never completes.
Has anyone ever made this work? And if so, can you please post how?
Hopefully can pass through the Epygi as it was a pain in the butt to set up.

Take a look at my post

I did something similar to forward calls the the customers answering service. They use analog lines. You can probably change the code to dial your PRI.

Do you have to dial the # sign at the end to forward there?
For us to forward to phone number “12345678”, we need to dial *2112345678# (this is *21#)
Will give your code a try later and see if it works.

I do not have to dial the #. BTW, I am in the states.