It seems that those seeking Mojolicious wisdom are best served on its mailing list. Here is a link to a discussion about Mason that took place on the list earlier in the year. From the discussion I gather that github is where you'll have to go to get the distribution for Mason integration, but if that's the case you ought to be able to unpack it, make, make test, and make install.
You may want to ask your question directly to that list rather than just reading over an old post. People get their Mojolicious answers within minutes there, sometimes from Sebastian himself.