ASPEN ksh and A__z variable

[Jim Smithson]

Here is a weird problem. I am running ASPEN KSH on an NCR Tower 32/650
under UNIX Sys V rel. 02.01.01. After installing ASPEN KSH I noticed
that my `at` jobs no longer worked. I have tracked the problem down
to the following bogus line in the job file which resides in direcctory
/usr/spool/cron/atjobs. 

	export A__z; A__z="! MAIL="*TMOUT=! HOME="

Note that most of the strings match the variables which should be "readonly".

The problem with this line is the 3 double quotes. When /bin/sh
subsequently executes the job file it has an unmatched ".
I have no idea where this variable A__z came from and even weirder is that
I cannot unset it with `unset A__z`. STILL stranger is I can define another
A__z variable and not affect the original one. (see following)

< just after login >
INPUT>	env | grep A__z
A__z=! MAIL="*TMOUT=! HOME=
INPUT>	set |grep A__z			<- Note: no output
INPUT>	A__z="Why Me?";export A__z
INPUT>	env | grep A__z
A__z=! MAIL="*TMOUT=! HOME=	<--------
INPUT>	set |grep A__z		        |- Why the difference?
A__z=Why Me?			<--------
INPUT>	unset A__z
INPUT>	env | grep A__z
A__z=! MAIL="*TMOUT=! HOME=
INPUT>	set |grep A__z

Obviously `set`(ksh builtin) and `/bin/env` don't agree on the value of
shell variable A__z. Is A__z a "shell variable"?
How can I get rid of this trash variable? How did it get in my environment?
Any help would be appreciated.

As an aside, the use of `at` on System V release 2 should only be allowed
to those who are to be trusted as root. There is a backdoor method of becoming
root using the `at` command.
-- 
James R. Smithson	Ascom Autelca AG      CH-3073 Guemligen/Switzerland
E-mail: jsmithso at aut.UUCP   FAX: +41 31 527 745   Voice : +41 31 529 214
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