[Samba] "guest ok = no" but guest user is used

[Claude Frantz]

I'm using version 2.2.7a.

In smb.conf there is:
in [global]
	security = USER
	guest ok = No
	guest account = nobody

There is not "guest ok" in  [printers].

Now I find print jobs which are supplied as user "nobody" to
the UNIX printing system, although the variable %U is set to
the real user name.

What is wrong here ?

Claude