[Samba] Problem mapping to public share from XP

[Swenson, Chris]

I have a stand alone RH ES 3 server which handles student email and a home
directory for each student.  It is not linked to the Active Directory side
of my house and it does not need to be.  No student accounts are in Active
Directory.  They exist solely on this Server.

I am running Samba 3.0.4  (The upgrades after this have caused problems with
how I create accounts and set passwords)

Within this setup we have a share called Common that anybody is free to map
to and deposit or withdraw files.  There is no user name or password
required to reach this share.  The users should be able to browse to it.

The problem is on some PC's when I map the drive it works fine, I am not
prompted for a user name or password. 
On some PC's when I map the drive I am prompted for a user name and
password. (Win XP or home or W2k, it makes no difference)  
Any legit username/password combo on the server will work, but according to
the politics of the situation that is not sufficient.  IT must be no
username or password prompting.  I suspect it is something on the windows
side.

Here are some particulars.

# workgroup = NT-Domain-Name or Workgroup-Name
   workgroup = CURRYNET

# server string is the equivalent of the NT Description field
   server string = Stumail Server

# This option is important for security. It allows you to restrict
# connections to machines which are on your local network. The
# following example restricts access to two C class networks and
# the "loopback" interface. For more examples of the syntax see
# the smb.conf man page
  hosts allow = 192.168. 10.16. 127.

;  guest account = pcguest

# Cause this host to announce itself to local subnets here
;   remote announce = 192.168.1.255 192.168.2.44

[common]
	path=/home/patches/common
	public = yes
	only guest = yes
	writable = yes
	printable = no

thanks for any advice.

Chris S.