Merged revisions 249893 via svnmerge from

Merged revisions 249893 via svnmerge from
https://origsvn.digium.com/svn/asterisk/trunk

........
  r249893 | dvossel | 2010-03-02 13:08:38 -0600 (Tue, 02 Mar 2010) | 11 lines

  fixes adaptive jitterbuffer configuration

  When configuring the adaptive jitterbuffer, the target_extra
  value not only could not be set from the configuration, but was
  not even being set to its proper default.  This value is required
  in order for the adaptive jitterbuffer to work correctly.  To resolve
  this a config option has been added to expose this value to the conf
  files, and a default value is provided when no config specific value
  is present.
........

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@249895 65c4cc65-6c06-0410-ace0-fbb531ad65f3