Comment 19 for bug 903422

libmtp is involved in MTP support because udev rules and protocol implementation are provided by that package, so bundling a recent one is required.
There are a few open Android 4 related bugs in its bug tracker (I can't link to them in this bug's meta because LaunchPad think that the bug tracker is at LaunchPad and refuses to monitor SourceForge ones):
http://sourceforge.net/tracker/?func=detail&aid=3489472&group_id=158745&atid=809061
Some are recently fixed (January):
http://sourceforge.net/tracker/?func=detail&aid=3456722&group_id=158745&atid=809061