cupsys: errors adding printer

I'm getting the following trying to add a printer through the cups web interface
in dapper:

E [08/Dec/2005:16:04:36 +0000] [cups-driverd] Unable to open driver directory
"/usr/lib/cups/driver": No such file or directory
I [08/Dec/2005:16:07:02 +0000] Started "/usr/lib/cups/cgi-bin/admin.cgi" (pid=9348)
E [08/Dec/2005:16:07:02 +0000] add_printer: not authorized!
I [08/Dec/2005:16:07:02 +0000] Setting Samsung_ML-1710 device-uri to
"usb://Samsung/ML-1710" (was "file:/dev/null".)
I [08/Dec/2005:16:07:02 +0000] Setting Samsung_ML-1710 printer-is-accepting-jobs
to 1 (was 0.)
I [08/Dec/2005:16:07:02 +0000] Setting Samsung_ML-1710 printer-state to 3 (was 5.)
E [08/Dec/2005:16:07:02 +0000] PPD file for Samsung_ML-1710 cannot be loaded!
E [08/Dec/2005:16:07:02 +0000] Missing value string on line 659.
I [08/Dec/2005:16:07:02 +0000] Hint: Run "cupstestppd
/etc/cups/ppd/Samsung_ML-1710.ppd" and fix any errors.
I [08/Dec/2005:16:07:02 +0000] Saving printers.conf...
I [08/Dec/2005:16:07:02 +0000] New printer 'Samsung_ML-1710' added by 'root'.

And when I try to print I'm getting this:

I [08/Dec/2005:16:18:21 +0000] Adding start banner page "none" to job 14.
I [08/Dec/2005:16:18:21 +0000] Adding end banner page "none" to job 14.
I [08/Dec/2005:16:18:21 +0000] Job 14 queued on 'Samsung_ML-1710' by 'jman'.
I [08/Dec/2005:16:18:21 +0000] Started filter /usr/lib/cups/filter/pdftops (PID
10030) for job 14.
I [08/Dec/2005:16:18:21 +0000] Started filter /usr/lib/cups/filter/pstops (PID
10031) for job 14.
I [08/Dec/2005:16:18:21 +0000] Started backend /usr/lib/cups/backend/usb (PID
10032) for job 14.
E [08/Dec/2005:16:18:21 +0000] [Job 14] pdftops-options: -cfg /etc/cups/pdftops.conf