Merged revisions 122919 via svnmerge from

Merged revisions 122919 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
r122919 | file | 2008-06-16 09:31:09 -0300 (Mon, 16 Jun 2008) | 6 lines

Only compare the first 15 characters so that even if the charset is specified we still accept it as SDP.
(closes issue #12803)
Reported by: lanzaandrea
Patches:
      chan_sip.c.diff uploaded by lanzaandrea (license 496)

........

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@122920 65c4cc65-6c06-0410-ace0-fbb531ad65f3