Merged revisions 219519 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r219519 | dvossel | 2009-09-18 18:19:50 -0500 (Fri, 18 Sep 2009) | 9 lines
  
  iax2 frame double free
  
  The iax frame's retrans sched id was written over right
  before iax2_frame_free was called.  In iax2_frame_free that
  retrans id is used to delete the sched item.  By writing over
  the retrans field before the sched item could be deleted, it was
  possible for a retransmit to occur on a freed frame.
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@219520 65c4cc65-6c06-0410-ace0-fbb531ad65f3