Merged revisions 81367 via svnmerge from

Merged revisions 81367 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r81367 | crichter | 2007-08-30 10:31:59 +0200 (Do, 30 Aug 2007) | 11 lines

Fixed a severe issue where a misdn_read would lock the channel, but read would
not return because it blocks. later chan_misdn would try to queue a frame like
a AST_CONTROL_ANSWER which could result in a deadlock situation. misdn_read
will now not block forever anymore, and we don't queue the ANSWER frame at all
when we already was called with misdn_answer -> answer would be called twice.

Also we don't explicitly send a RELEASE_COMPLETE on receiption of a RELEASE
anymore, because mISDN does that for us, this resulted in a problem on some
switches, which would block our port after some calls for a short while.

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@81368 65c4cc65-6c06-0410-ace0-fbb531ad65f3