[Asterisk-Users] "auto fallthrough" hangup on 1.2.1

[Pisac]

I upgraded from 1.0.9 to 1.2.1
My IVR which worked perfectly on 1.0.9, now hangup with no reason (at
least I could not find a cause)

When this hangup happen, I can read:
== Auto fallthrough, channel 'IAX/user-20' status is 'BUSY'
This happening also with ZAP channels

I'm really disappointed with 1.2.1, what is benefit from upgrade if I
must spend couple days to get my system to work as it worked previously
before "upgrade" (I think it should be named "troublegrade").