Merged revisions 301134 via svnmerge from

Merged revisions 301134 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.8

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  r301134 | rmudgett | 2011-01-07 19:11:31 -0600 (Fri, 07 Jan 2011) | 7 lines

  The DTMF attended transfer feature cannot callback a chan_dahdi BRI phone.

  The DAHDI ISDN channel name is not dialable.

  Make a channel name like DAHDI/i3/400-12 dialable when the sequence number
  is stripped off of the name.
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@301135 65c4cc65-6c06-0410-ace0-fbb531ad65f3