Strickly for old timers

An old story that goes like this

18 Mars years ago, just starting work on the AS/400 , I looked for an
equivalent to the S/36 's
IF_ACTIVE OCL. (For younger folks, this feature lets you check if a program
is already running so you don't submit it a again)
I failed, then and on later tries.
However, seeing the (relative) new STACK_INFO and ACTIVE_JOB_INFO SQL
services
I thought I'd combine the two to finally get my IF_ACTIVE.
So here is an SQL that I think should accomplish it but does not:

SELECT PROGRAM_NAME, PROGRAM_LIBRARY_NAME
FROM TABLE(QSYS2.STACK_INFO((SELECT distinct JOB_NAME
FROM TABLE(QSYS2.ACTIVE_JOB_INFO(JOB_NAME_FILTER => '*ALL'))) ,'ALL')) A
where PROGRAM_NAME = 'NMFCTLLST'

I get a "Result of SELECT more than one row"

Any ideas, anyone?

TIA
Gad