Dial string change

have set up astpp and all is working ok however when I try to make calls via a dialer I need to dia for example 44203454545
this is a problem because if I want to dial a number out of my address book they all start with 0044203454545.

Can someone tell me how I can change this to dial the complete number with 00 but then I need to strip it and send 44203545454 to Provider ???

thanks
Adrian

You are looking to dial with a “prefix.” In your case 00 is the prefix.

FreeSwitch uses Regular expressions to accomplish this

https://freeswitch.org/confluence/display/FREESWITCH/Regular+Expression