Merged revisions 270980 via svnmerge from

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

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  r270980 | qwell | 2010-06-16 16:10:09 -0500 (Wed, 16 Jun 2010) | 4 lines
  
  Need to lock the agent chan before access its internal bits.
  
  Pointed out by russellb on asterisk-dev mailing list.
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@270981 65c4cc65-6c06-0410-ace0-fbb531ad65f3