When an external parser parameter is specified for a job run with the DRMAA executor, the filetype is not found when executing the stage. This is due to the UniversalParser failing to call DocumentStreamParser addExternalParsers in the case where the internal parameters do not have a key named "parse".
To ship in 12/2014 release.
Associated UniversalParserTest had a separate bug that masked this issue. Test fixed.