Preventing a recursive call...

Hi All,

        Does anybody have a clue as to how I can prevent a recursive call
from a command?

        The scenario is.... I have a command which calls a CL(1) which calls
a CL(2) which calls an RPG... at this point it's allowed, and common, to get
to a command line, where everybody forgets that they've called the command
once already - calling the command again generates a recursive call error in
the RPG program...

        I've searched the archives and tried every combination of MONMSG's
and *PSSR's that I can come up with, yet the error prevails...

        Any ideas on how I can get the first CL(1) to end if the command is
already in effect (or running, or whatever)?

        TIA,
                Jerry