Merged revisions 79857 via svnmerge from

Merged revisions 79857 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r79857 | russell | 2007-08-17 08:37:08 -0500 (Fri, 17 Aug 2007) | 5 lines

Fix some crashes in chan_sip.  This patch changes various places that add items
to the scheduler to ensure that they don't overwrite the ID of a previously
scheduled item.  If there is one, it should be removed.
(closes issue #10391, closes issue #10256, probably others, patch by me)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@79858 65c4cc65-6c06-0410-ace0-fbb531ad65f3