[Asterisk-Users] Call transfer - (Call failed)

[Giuseppe]

Hi,
I'm trying to call an extension and then transfer the call
to another extension, but something strange happens.

This is the extension:
exten => _9.,1,Dial(CAPI/ISDN4/${EXTEN:1}/b,tT)

When I dial any number starting with 9, I always
get CALL FAILED, but the called party still receive
the call and hears silence forever.
Does anyone know why?

Giuseppe