[Samba] Samba printing crashes all inet services

[Martin E. Main]

Hi,
 
I have a rather unusual problem with samba printing, which pulls down
all networking services on my linux box. 
 
I have a Linux box running FC4 running samba 3.0.14a
 
I have Canon Pixma ip1200 inkjet connected via usb and running under
cups.
 
Printing from a Windows XP box works whenever I run test print and
thereafter, but leave it a couple of days and I try and print again, the
printer stops after printing a couple of lines, then all network
services on the Linux box die. As the Linux box has no monitor /
keyboard, I end up having to power down from the front panel as I lose
sshd services (my normal method of accessing the Linux box)
 
The only thing that I have managed to trace in smbd.log is as follows:-
 
[2006/12/29 09:37:28, 1] smbd/service.c:make_connection_snum(642)
  martin (192.168.10.2) connect to service canon_inkjet initially as
user mmain (uid=0, gid=500) (pid 23041)
[2006/12/29 09:37:28, 0] smbd/nttrans.c:call_nt_transact_ioctl(2317)
  call_nt_transact_ioctl(0x280004): Currently not implemented.
 
Nothing of significance in the main system logs
 
My smb.conf is as follows:-
 
# Global parameters
[global]
        workgroup = MAINS
        server string = Linux Server
        interfaces = eth0
        obey pam restrictions = Yes
        pam password change = Yes
        passwd program = /usr/bin/passwd %u
        passwd chat = *New*password* %n\n *Retype*new*password* %n\n
*passwd:*all*authentication*tokens*updated*successfully*
        username map = /etc/samba/smbusers
        unix password sync = Yes
        log file = /var/log/samba/%m.log
        max log size = 0
        name resolve order = lmhosts hosts wins bcast
        time server = Yes
        socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
        printcap name = /etc/printcap
        disable spoolss = Yes
        add machine script = /usr/sbin/useradd -d /dev/null -g
samba-clients -s /bin/false -M %u
        domain logons = Yes
        preferred master = Yes
        domain master = Yes
        ldap ssl = no
        admin users = administrator, mmain
        cups options = raw
 
[canon_inkjet]
        comment = Canon iP1200
        path = /var/spool/samba
        guest ok = Yes
        printable = Yes
        printer name = Canon
        use client driver = Yes
 

Any suggestions or hints I can follow, most appreciated.
 
Many Thanks,
 
Martin