Merged revisions 318919 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r318919 | bbryant | 2011-05-13 14:04:50 -0400 (Fri, 13 May 2011) | 10 lines
  
  This patch fixes an issue with SRTP which makes HOLD/UNHOLD impossible when too
  much time has passed between sending audio.
  
  (closes issue #18206)
  Reported by: bernhardsi
  Patches: 
        res_srtp_unhold.patch uploaded by bernhards (license 1138)
  Tested by: bernhards, notthematrix
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@318920 65c4cc65-6c06-0410-ace0-fbb531ad65f3