Merged revisions 162286 via svnmerge from

Merged revisions 162286 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r162286 | russell | 2008-12-09 14:57:35 -0600 (Tue, 09 Dec 2008) | 9 lines

Fix an issue where callers on an incoming call on an SLA trunk would not hear ringback.

We need to make sure that we don't start writing audio to the trunk channel until we're
actually ready to answer it.  Otherwise, the channel driver will treat it as inband
progress, even though all they are getting is silence.

(closes issue #12471)
Reported by: mthomasslo

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@162291 65c4cc65-6c06-0410-ace0-fbb531ad65f3