Ringback to External Callers when Hold Recalls

[Boris]

This is an odd one.  We recently upgraded 3300's/vMCD's to 8.0 SP2 and now when someone puts an external call on hold, there is no ringback to the external caller to let them know hold time has expired.  The customer wants the outside caller to hear Ring Back when the hold timer expires.  I would think that this was an 8.0 SP2 issue, but I've had another person tell me that they have seen this before in previous versions and never found a fix.  I have a ticket going with Mitel, but the process is rather slow because it is being handled in India.

Has anyone seen this and/or found a fix for it?

[Dogbreath]

Yes, I have had this issue reported by users on 7.1 PR2 with a SIP trunk ["Avoid signalling hold to peer" is no - should probably tweak that and re-test]. The issue was not reported for >1yr after the system was updated to 7.1 PR2 so don't actually know how long it has been present.

[Boris]

Nope, these are all PRI's.  The only IP traffic is between the phones and the systems.  I too have fought the SIP battle before.