samba - Mar 2005 - samba authentication behaves differently between windows and samba clients

Hello,

 I'm using samba 3.0.11 and SuSE Enterprise Server 8 (SLES8). All
authentication tests using sambaclient works as expected, I can 
authenticate logon requests, but when I use windows 98 clients
authentification fails with some password lenghts  :-?. I know 
it sounds weird but I can reproduce it as many times as I want.

i.e:

password "aaa" -> smbclient - always works
               \> windows 98 - always works

password "aaaa" -> smbclient - always works
                \> windows 98 - always fails

This makes sense to someone? 
I'm out of ideas and all suggestions and comments will 
be welcome, thank you.

log of a successfull login session:
http://195.55.55.164/tests/samba/yes.txt
and of a failed one:
http://195.55.55.164/tests/samba/no.txt

# testparm
Load smb config files from /etc/samba/smb.conf
Processing section "[homes]"
Processing section "[netlogon]"
Loaded services file OK.
Server role: ROLE_DOMAIN_PDC
Press enter to see a dump of your service definitions

# Global parameters
[global]
        workgroup = BETA
        interfaces = 127.0.0.1, eth0
        bind interfaces only = Yes
        passdb backend = ldapsam:ldap://atlas.servidores.fadesa
        log level = 3 passdb:50 auth:50 winbind:2
        use spnego = No
        client use spnego = No
        socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
        load printers = No
        logon script = inicio.bat
        logon path = \\%N\profiles\%U
        logon drive = H:
        domain logons = Yes
        os level = 33
        preferred master = Yes
        domain master = Yes
        wins support = Yes
        ldap admin dn = cn=ora9i,ou=maquinas,ou=cuentas,dc=fadesa,dc=es
        ldap group suffix = ou=grupos
        ldap idmap suffix = cn=idmap,ou=samba,oui=aplicaciones
        ldap machine suffix = ou=maquinas,ou=cuentas
        ldap passwd sync = Yes
        ldap suffix = dc=fadesa,dc=es
        ldap ssl = no
        ldap user suffix = ou=personas,ou=cuentas

[homes]
        comment = Home Directories
        path = /samba/%u
        valid users = %S
        read only = No
        browseable = No

[netlogon]
        comment = The domain netlogon service
        path = /tmp
        read only = No
        guest ok = Yes
        browseable = No


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