This patch didn't make it into 1.2.0, but is in asterisk CVS for 1.2.1, it appears to be fairly serious for anyone who uses SIP w/RFC2833 DTMF (which is mostly everyone). Trivial patch from here: http://bugs.digium.com/view.php?id=5780
the patch was already in the first patchset (asterisk-1.2.0-patches-1.0), but one of the patchutils truncated the file... ebuild and patchset have been updated