gargoyle: only grab the "-jN" option from MAKEOPTS and pass it to jam
drwxr-xr-x - dev-games
drwxr-xr-x - dev-lang
drwxr-xr-x - games-engines
drwxr-xr-x - games-util
drwxr-xr-x - licenses
drwxr-xr-x - metadata
drwxr-xr-x - profiles
drwxr-xr-x - virtual