Merged revisions 301845 via svnmerge from

Merged revisions 301845 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r301845 | bbryant | 2011-01-14 14:35:23 -0500 (Fri, 14 Jan 2011) | 9 lines

  Fix for a consistent MulticastRTP channel driver crash due to use of unitilized
  data.

  (closes issue #18290)
  (closes issue #18602)
  Reported by: voipgate, wybecom

  Review: https://reviewboard.asterisk.org/r/1076/
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@301847 65c4cc65-6c06-0410-ace0-fbb531ad65f3