Merged revisions 311297 via svnmerge from

Merged revisions 311297 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r311297 | rmudgett | 2011-03-17 21:59:05 -0500 (Thu, 17 Mar 2011) | 12 lines

  Race condition when ISDN CallRerouting/CallDeflection invoked.

  The queued AST_CONTROL_BUSY could sometimes be processed before the
  call_forward dial string is recognized.

  * Moved setting the call_forwarding dial string after sending a response
  to the initiator and just queue an empty frame to wake up the media thread
  instead of an AST_CONTROL_BUSY.

  * Added check for empty rerouting/deflection number and respond with an
  error.
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@311298 65c4cc65-6c06-0410-ace0-fbb531ad65f3