Merged revisions 315501 via svnmerge from

Merged revisions 315501 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r315501 | tilghman | 2011-04-26 14:18:46 -0500 (Tue, 26 Apr 2011) | 14 lines

  Fix the bounds-checking code.

  The code that set the bit within the select bitfield was correct, but the
  bounds-checking code was not.  The change to that line uses the new _bitsize
  macro for clarity.  Also, FD_ZERO macro did not zero-out anything but the
  first word of the bitfield, so this could have caused problems with modules
  using that macro with the expanded bitfield.

  (closes issue #18773)
   Reported by: jamicque
   Patches:
         20110423__issue18773.diff.txt uploaded by tilghman (license 14)
   Tested by: chris-mac
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git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@315502 65c4cc65-6c06-0410-ace0-fbb531ad65f3