CCL: shifting coordinates with CHARMM



Hi,
 is it possible to re-center coordinates with CHARMM?  Some viewing programs
 are not aware of PBCs and during a simulation the system of interest may
 diffuse to the edges of the box.  It might be useful, therefore, to shift an
 atom (or maybe an arbritary point in space) to the center of the box.
 TIA,
 Hannes.