hmm, hmm, you misunderstood !
Actually, the 1st script i wrote for automatic installation did not handle the installation of mplayer-mt/mencoder-mt but the new one i did release for about 2 months now tries to install the mplayer-mt and mencoder-mt if your system can support them.
In other words, i personally don't built any kind of mplayer-mt or mencoder-mt package (really tricky and busy project since i don't really have much time these later days

Anyway, if i were you, i would wait someone to build those packages for lastet Ubuntu versions. We don't really have the choice apart from building from the source.