search for: nxxnxxxx

I'm trying to write some dialplan patterns to allow my users to control call forwarding from their handsets. Right now, I have this in extensions.conf: [forwarding] exten => _*21*X.X*,1,Macro(set-cfim,${CALLERIDNUM},${EXTEN:4}) I was hoping that this would match any string of the form *21*nnn*, where nnn is 3 or more digits. But Asterisk seems to ignore the final X*, and allows it to