Why have my lpr queues disappeared?

[bill purvis]

My printer is connected to a server machine, running Mandrake.
When I installed Ubuntu it probed the network and discovered the
print queues and set up cups accordingly. I was able to use lpr
to print things with the only problem being there was no default
print queue - I have three queues set up on the server, all going
to the same printer but with A3, A4 and glossy having different
attributes. I figured out how to get various things to include
-Pa4 on the lpr command (for example gv) and this worked fine until
the last day or so. Now I get 
	Unknown destination "a4"!
and similar for the other two queues.
I tried restarting CUPS but that made no difference. I can bring up
the CUPS configuration on my browser (http://localhost:631) and it
show all three print queues. The 'print a test page' works so 
it's something on this side that's gone awry.

After some rooting about I discovered there is a printcap file
(/var/run/cups/printcap) which lists the queues, so presumably I
could edit that and make a4 the default, if I could remember the
right format for it. This says it has been derived by cups from
/etc/cups/printers.conf, but that doesn't exist on this machine,
though there is one on the server (which, incidentally specifies a4 as
the default printer).

Anyone well up on lpr/lpq and understand the interaction between them
and cups?

For the moment, I am having to copy stuff across to the server and lpr
them from there.

Bill
-- 
+---------------------------------------+
| Bill Purvis, Amateur Mathematician    |
|  email: bil at beeb.net                  |
|  http://bil.members.beeb.net          |
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