Hello, v4.0.0 of ParmEd, getting

AttributeError: 'Rst7' object has no attribute 'reshape'

when trying to run OpenMM with restraints. The pmemd/sander input file contains (just showing the restraint specific options)

ntr=1,
restraintmask='@CA,C,N,O',
restraint_wt=1.0,

And I'm passing reference coords with the -ref argument, e.g.
OpenMM -i md_openmm.in -o md.mdout -r md.rst7 -x md.nc -ref min.rst7 -O script openmm_run.py