There is one point in (future stable) kaffeine that needs attention
imho. Due to an update in shared-mime-info (migrated to testing ...
hmm ... some time ago :), the mimetypes specified in the
kaffeine.desktop file don't assign .m2t files to kaffeine. This is
bad, because kaffeine creates such files (and users expect that they
can open these files without trouble - currently an 'open with' dialog
The fixing changeset is , also part of the recent 1.1 release.
 http://websvn.kde.org/?view=revision&revision=1137341 (the first
part - modification of kaffeine.desktop - is sufficient).