CallManager 4.1(3). Here is the scenario. Calls from the PSTN hit Unity-PSTN Caller Dials Extension-call transferred and answered on PhoneA-PhoneA transfers to PhoneB and Answered-PhoneB transfers PSTN call back to PhoneA-Phone A answers but call Drops either in a Blind or Supervised transfer. Happens everytime. Attached is a debug from the PSTN. Reading the debug isdn q931 all I can notice at the end was this: Protocol error; unspecified after the last transfer. Any thoughts would be great. Thanks.