It seems the entire template engine system has been overhauled in express 3.x:
template engine compliance from engine.compile(str, options) => Function to engine.__express(filename, options, callback)
https://github.com/visionmedia/express/wiki/Migrating-from-2.x-to-3.x
It seems the entire template engine system has been overhauled in express 3.x:
https://github.com/visionmedia/express/wiki/Migrating-from-2.x-to-3.x