Konica-Minolta bizhub C250 will not print from computer via IP network

Can anyone help me get this silly machine to print a basic test page from a
Windows XP Pro machine, via our IP intranet?
My friend's C250 has served for years as a reliable copier. Now we want to
use it as a network printer.

We have installed the relevant drivers, from the bizhub's CDROM collection,
to a new WinXP Pro computer named "Gamma." We installed into Gamma the
Windows capabilty to print to an LPR printer, first by adding "Print
Services for Unix" in the XP Control Panel; then by adding the printing
device "locally" that is an LPR with the relevant IP address... and
hostname. The "address of the server providing lpd" is 192.168.1.81. The
"name of the printer on that server" is KMBT560A94. I must wonder about
that hostname, which comes to us as a "given." I was not able to assign a
hostname into the bizhub, as I have successfully done with various
ip-accessible print servers that attach to printers.

I ping the ip address 192.168.1.81 successfully, every time, from the
computer.

When I print a test page to this LPR printer, there is a brief spooling
action under Windows Control Panel ...printers. The job seems to go through
perfectly...at the computer, at least. The document number rises from 0 to
1, and then goes back to 0. The document name flashes briefly in the
printer's queue, before disappearing, as should be the case when a job turns
into hard copy at a printer.

The only problem is that no print job EVER emerges. 100% failure.

Any suggestions would be appreciated.

My friend, who owns the machine, and who is "non technical," wonders if he
might need to "log into" the bizhub, at its key panel, in order to get print
jobs to come out. Meanwhile, the machine works fine as a copier, without
any ip involvement.

P.S. Some time ago, I got into the keypanel of this machine, changed the
password, and entered the ip address shown above. I enabled the "ping"
reaction, too.

THANK YOU.