Null password question

[David Lambert]

I am quite a newbie to samba, so please excuse if this is a trivail question, 
but I cannot find the answer in the archives.
My problem is that I would like to completely kill null passwords. I have 
tried all sorts of combinations in my smb.conf file, but the only thing that 
seems to work reliably is to set the guest account to some bogus name. This 
seems to me not the "correct" way to do this. Could someone pleas point tme 
in the right direction? The global portion of my smb.conf file follows:

; Configuration file for smbd.
; ============================================================================
;
[global]
   # Use encrypted passwords
   encrypt passwords = yes
   # Disallow NULL passwords
   guest account = xxxxxx
   null passwords = no
   workgroup = WORKGROUP
   netbios name = DOCUSERV
   server string = Document Server
   interfaces = 192.168.1.0/24 192.168.0.0/24
   security = user
   load printers = no
   log level = 2
;  This next option sets a separate log file for each client. Remove
;  it if you want a combined log file.
   log file = /usr/local/samba/var/log.%m



TIA

Dave.