I recently encountered a situation that I simply can not explain. In
certain situations, my session becomes unable to set a boolean variable to
FALSE. Doesn't matter if it is a CI variable like HPCMDTRACE or one of my
own creation.  Doesn't matter if already existed or was created for the
first time by my "setvar".

I can do the following:

SETVAR  ISITSO,FALSE
SHOWVAR  ISITSO

and the result is:
ISITSO = TRUE

How could this ever happen?

Possible background info:
This just began happening after I started testing a demo of a product
mentioned on this list, namely: ScreenJet. I am not pointing any fingers
here; coincidences happen all the time. I have submitted this question to
the makers of ScreenJet, but thought I would run it by the astute members
of this list; since I could not conceive how anything could cause this
phenomenon to occur.