Don't think you are going to have much luck at making anything like an oktoberfest even in ale form from extract... You would at least need to mash the munich I would think to get the maltiness...
Williams Brewing has an extract they call German Gold that they say is made from Munich and Pils malts//http://www.williamsbrewing.com/GERMAN_GOLD_EXTRACT_6_LBS_P362C99.cfm.