To my knowledge this is the only way it is possible.  I have done some
elaborate similar things.  The best thing is to do make the script
executable by a group and not readable because the userid and password will
be in there.  I have found however that dsmadmc requires root access because
of the ShMem access so we use sudo.  That secures it even further because
the person can be authorized only to execute the specific script.  I am sure
there are ways around the root access requirement for the shared memory.

Paul D. Seay, Jr.
Technical Specialist
Naptheon, INC
757-688-8180