Merged revisions 89037 via svnmerge from

Merged revisions 89037 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r89037 | russell | 2007-11-06 12:20:07 -0600 (Tue, 06 Nov 2007) | 11 lines

If someone were to delete the files used by an existing MOH class, and then
issue a reload, further use of that class could result in a crash due to
dividing by zero.  This set of changes fixes up some places to prevent this
from happening.

(closes issue #10948)
Reported by: jcomellas
Patches:
      res_musiconhold_division_by_zero.patch uploaded by jcomellas (license 282)
	  Additional changes added by me.

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@89038 65c4cc65-6c06-0410-ace0-fbb531ad65f3