Merged revisions 230881 via svnmerge from

Merged revisions 230881 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

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  r230881 | file | 2009-11-23 09:45:45 -0600 (Mon, 23 Nov 2009) | 7 lines

  Change fax detection in chan_sip so it behaves as one would expect.

  Internally the way T.38 is negotiated has changed and the option no longer
  reflects a behavior that is valid. It will now look for a CNG tone on
  received calls and if present send the call to the 'fax' extension. It is
  then up to the application or channel to request the switch over to T.38.
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.1@230883 65c4cc65-6c06-0410-ace0-fbb531ad65f3