[Samba] Server crash results in no printing (SuSE, Samba 3.0.4)

[Gareth Robert Halfacree]

(yes, I know it's an old version of Samba but I *really* don't want to 
mess about upgrading right now)

The server in question (SuSE Enterprise Linux 9) got itself in a tizz 
last night and was restarted cleanly via the shutdown -r command this 
morning.  Everything comes back up, including Samba, and all is fine.

Except that no-one can print.

Nothing has changed in any of the configuration files.  tdbbackup 
reports that all the tdb files are intact.

Printing from the cups web interface ('Print Test Page') works fine. 
Printing when logged on as 'administrator' works fine.  Printing as a 
Joe-Blow user fails miserably.

I'm getting the following error message in the logs:

[2006/01/26 08:48:58, 0] printing/print_cups.c:cups_queue_get(903)
   Unable to get jobs for ipp://localhost/printers/IT_Office - 
client-error-not-authorized

I'm also seeing a number of:

process_request_pdu: failed to do schannel processing

This thing is kicking my hindquarters, and as it's the central 
logon/print server for a not-small educational establishment the 
pressure is on to get it sorted.

I've doubled-checked all the configuration files, scanned the tdb files 
with tdbbackup, restarted the smbd process after clearing out the 
volatile tdbs, and googled my little heart out.

Any ideas?

-- 
Gareth Halfacree
http://gareth.halfacree.co.uk