remote downlevel document

Archived from groups: microsoft.public.win2000.security (More info?)

Hi,
our printers suddenly print some nonsense characters on papers and this is
logged as "remote downlevel document owned by x printed x pages/bytes..." on
system event log of print servers with event ID 10. The users are just a few
persons we saw from log detais and they all have local admin rigths on their
domain machines. We scanned for virus/worm on their machines, but nothing is
detected (machines are clean). we also scanned for spywares with MS anti
spyware beta and spybot and they detected nothing. Now what can be the
problem of this strange printing attempts?? Printing attempts start nearly
synchronously from these few users who are located at different sites. We
still suspect of some triggering malicious mechanism embedded in some
software... Any help/idea would be very userful. thanx.
atx.