Merged revisions 67119 via svnmerge from

Merged revisions 67119 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r67119 | russell | 2007-06-04 17:28:55 -0500 (Mon, 04 Jun 2007) | 6 lines

Add comments for two functions that get called with the appropriate call locked,
but perform operations that could result in the pvt structure getting destroyed
before returning again, causing numerous seg faults all over the module.
(inspired by issues #9642, #9569, and #9666, and the work done by stevedavies
 and mihai)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@67120 65c4cc65-6c06-0410-ace0-fbb531ad65f3