CUPS: Parallel port busy; will retry in 30 seconds...

[DvB <dvanbalen@jam.rr.com>]

I keep getting this error when attempting to print to my HP DeskJet 932C
from the cups web interface or with lp. When I cat a file to /dev/lp0, I
get: "bash: /dev/lp0: Device or resource busy." Needless to say, the jobs 
never print.
Another thing I noticed is that, even after canceling a job, files with
names like c0000N (where N is the same number as the job I just
cancelled... for e.g. lp0-6 will become c00006) are left in
/var/spool/cups and /var/spool/cups/tmp is full of files that start with
"gs."

I've tried all the drivers for 932C and also a couple for 930C, which is
what /proc/sys/dev/parport/parport0/autoprobe seems to think my printer
is:

CLASS:PRINTER;
MODEL:DESKJET 930C;
MANUFACTURER:HEWLETT-PACKARD;
DESCRIPTION:Hewlett-Packard DeskJet 930C;
COMMAND SET:MLC,PCL,PML;

TIA