Cancelling print job

[Stephen Schroder <sschrode@xxxxxxxxxxx>]

Apsfilter is great software.  In three hours it solved
a problem I had been wrestling with for a month.  It
was so easy to setup.

There's one thing I still don't know how to do.  How
can I cancel a print job once it has been started. 
Even rebooting doesn't help, since the job apparently
has been spooled on the hard drive.  And the job
doesn't show up in Print Jobs or Printing Manager in
KDE in x-window.

Thanks,
Steve