[asterisk-users] FSK signal start after second ring

[zhao bo]

hi all
  my local PSTN use an different cid signalling format
[ring-DTMF-ring],and my asterisk server can not get the cid
info,allways say "UNKNOWN".I try to use EX220 (caller id converter)
translate   DTMF into FSK,but after that the signal looks like
[ring-DTMF-ring-FSK],asterisk still "UNKNOWN" .Is there someway that i
can tell asterisk that my fsk signalling start after second ring ?

sorry for my English!