SendDTMF( ) Sends arbitrary DTMF digits to the channel
SendDTMF(digits[,timeout_ms])
Sends the specified DTMF digits on a channel. Valid DTMF digits include 0-9, *, #, and A-D. You may also use the letter w as a digit, which indicates a 500-millisecond wait. The timeout_ms argument is the amount of time between digits, in milliseconds. If not specified, timeout_ms defaults to 250 milliseconds.
Returns 0 on success or -1 on a hangup.
exten => 123,1,SendDTMF(3212333w222w366w3212333322321,250)