Look in /etc/cups/ppd, is the PPD file there? Look at
/etc/cups/printers.conf, are there differences between the two
printers? Differences should probably occur, but make sure there
is nothing wrong with the C41UX entry.
Did you restart the CUPS daemon (cupsd) after installing the
Try setting the C41UX printer to be a file, and take a look at the
output from a test page.
Another possibility is that the PPD isn't correct for CUPS. Most
of the PPDs that I've used with CUPS have some nonstandard
entries (mostly concerning filters), and I guess if your PPD
doesn't have the necessary entries, it won't work. Try comparing
your C40UX PPD and the C41UX PPD and look for obvious
references to CUPS or Easy Software. . .