(I know this sounds crazy but ...)
 
As best that I can tell, our production MVS batch procedure (SYSTEM@PENNSTAT)
that spools a file to a LISTSERV list (xxxxxxx@PSUVM) had its contents
interpreted by LISTSERV as a command stream and consequently produced
results consistent with same returning them to [log in to unmask]
 
I've scanned our SYSLOGs (2 Members of Spool) searching for the strings
LISTSERV and xxxxxxx.  I can find the list name echoed via
 
  M0 File (nnnn) spooled to xxxxxxx -- origin PENNSTAT(SYSTEM)
 
Also, I've contacted the LISTSERV maintainer and the programmer of
the generated batch JCL and we can find no anomalies/changes to the
production code.
 
There were a number of successful distributions about that time too.
SYSTEM@PENNSTAT had not been served out (the actual file wasn't that
long, though multiple independent files have been generated i.e., it
seems like a fluke).
 
Anyone ever have a file sent to a list interpreted as commands?
 
/Pete ([log in to unmask])
--
Peter M. Weiss                     |              oas.psu.edu postmaster
31 Shields Bldg -- Penn State Univ.| "He was a couple of diskettes short
University Park, PA USA 16802-1202 |     of a complete hard disk backup"