Merged revisions 264331 via svnmerge from

Merged revisions 264331 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

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  r264331 | dvossel | 2010-05-19 14:21:04 -0500 (Wed, 19 May 2010) | 13 lines

  fixes crash in check_rtp_timeout

  During deadlock avoidance the sip dialog pvt is locked and
  unlocked.  When this occurs we have no guarantee the pvt's owner
  is still valid.  We were trying to access the pvt's owner after
  this without checking to see if it still existed first.

  (closes issue #17271)
  Reported by: under
  Patches:
        check_rtp_timeout.diff uploaded by under (license 914)
  Tested by: dvossel
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@264332 65c4cc65-6c06-0410-ace0-fbb531ad65f3