Merged revisions 250394 via svnmerge from

Merged revisions 250394 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r250394 | dvossel | 2010-03-03 12:02:27 -0600 (Wed, 03 Mar 2010) | 16 lines

  fixes problem with duplicate TXREQ packets

  When Asterisk receives an IAX2 TXREQ packet, try_transfer()
  will call store_by_transfercallno() to link the chan_iax2_pvt
  struct into iax_transfercallno_pvts. If a duplicate TXREQ
  packet is received for the same call, the pvt struct will be
  linked into iax_transfercallno_pvts multiple times.  This patch
  fixes this.  Thanks rain for debugging this and providing a patch!

  (closes issue #16904)
  Reported by: rain
  Patches:
        iax2-double-txreq-fix.diff uploaded by rain (license 327)
  Tested by: rain, dvossel
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@250395 65c4cc65-6c06-0410-ace0-fbb531ad65f3