minimize_ppi.mpi.linuxgccrelease doesn't use jd2?

mpiexec -np 8 $ROSETTA_BIN/minimize_ppi.mpi.linuxgccrelease -database $ROSETTA_DATABASE -l pdb.lst

runs each structure in the list 8 times instead of running one structure per processor, thus 8 structures simultaneously. But minimize.mpi.linuxgccrelease distributes the jobs via jd2 and runs 8 structures on 8 processors simultaneously. Any thoughts? Thanks!