The recommended version of Kdenlive is 0.9.2 and MLT 0.8.2
All the following packages have been built with the official ffmpeg version of each Ubuntu release. If you are using some backported version of ffmpeg you can't use those packages.
Please report any problem in our forum.
Versions of Kdenlive in official repositories are deprecated. It is strongly recommended to install Kdenlive 0.9 packages using Sunab's alternative repository:
Install Kdenlive with the Software center (11.04, 11.10, 12.04) or your favourite package manager.
Alternatively you can do all the process typing the following command line in a terminal :
sudo add-apt-repository ppa:sunab/kdenlive-release && sudo apt-get update && sudo apt-get install kdenlive