Merged revisions 186458 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

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  r186458 | kpfleming | 2009-04-03 15:19:20 -0500 (Fri, 03 Apr 2009) | 5 lines
  
  Fix a bug where DAHDI/Zaptel channels would not properly switch formats when requested
  
  Don't offer AST_FORMAT_SLINEAR on DAHDI/Zaptel channels... while it could provide a slight performance benefit, the translation core in Asterisk has some flaws when a channel driver offers multiple raw formats. this fix is much simpler than fixing the translation core to solve that issue (although that will be done later).
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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@186461 65c4cc65-6c06-0410-ace0-fbb531ad65f3