svn now includes full support for translating techtrees. Megapack was added to transifex so please translate megapack into your favorite language through transifex!
Thanks
P.S. People making techtrees can use mg to produce a 'default' techtree lng file via the commandline option:
megaglest --translate-techtrees=megapack
Substitute in your own techtree name and it creates the lang/megapack_default.lng with all entries