Merged revisions 339463 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/10

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  r339463 | irroot | 2011-10-05 08:28:46 +0200 (Wed, 05 Oct 2011) | 9 lines
  
  Only change the capabilities on the gateway when
  the session is been destroyed there is still
  a race condition that ends in a segfault.
  
  if the caps are changed the logic in res_fax_spandsp
  will run T30 code not gateway code to end the session.
  this has been experienced on a "slower" under spec system.
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@339464 65c4cc65-6c06-0410-ace0-fbb531ad65f3