Problem 2 is that doing a local hangup (eg. by writing "H" to the
dialout device) to a call which is already disconnected results in isdnd
moving the cfg entry to an illegal state, from which there is no
recovery. This is tricky because there is no way to synchronize local
hangup with the remote end (ie. the callee can always hang up at an
inconvenient time)! Hence, patch-2 alters fsm.c's EV_DRQ state table
such that the local hangup request is processed or ignored in most
states, even for disconnected calls.
Submitted by: Juha-Matti Liukkonen <jml@cubical.fi>
0bab8d6b8c