Packs the message base. This means that the deleted messages are effectively removed from the message base.
The following are valid options for PBUTIL MP:
(-)
-D .......................... Removes old messages. Check the section of
                              the manual about the message areas for more
                              information.
-F .......................... Forces the pack to be executed, even if
                              there are no deleted messages (Hudson Only)
-H .......................... Instructs the message packer to pack the
                              Hudson areas only.
-J .......................... Instructs the message packer to pack the
                              JAM areas only.
-K .......................... Deletes the .BAK files created when packing
                              the message base. (Hudson Only!)
-R .......................... Instructs the message packer to renumber
                              the message base.  Renumbering the message
                              base is done automatically when the highest
                              message number exceeds 25000.  Lastread-
                              pointers in the userfile will be adjusted
                              when renumbering.
Do NOT pack the message base when a user is online!!