As addition here the actual settings out of serveradmin:
root# serveradmin settings smb
smb:map to guest = "Bad User"
smb:LoggingLevel = 6
smb:MasterBrowser = "domain"
smb:SuspendServices = no
smb:VirtualAdminShares = no
smb:KerberosRealm = "HENK.MATZKE.INTERN"
smb:Workgroup = "matzke.intern"
smb:VirtualHomeShares = yes
smb:wins server:_array_index:0 = _empty_dictionary
smb:AllowLanManAuth = yes
smb:ServerDescription = "Mac OS X Server"
smb:LocalKerberosRealm = "LKDC:SHA1.BDDC6E3B5F2481012293BCB894456867C3B1440C"
smb:NetBIOSName = "henk"
smb:AllowNTLMAuth = yes
smb:setStateVersion = 2
smb:EnabledServices:_array_index:0 = "wins"
smb:EnabledServices:_array_index:1 = "wins"
smb:EnabledServices:_array_index:2 = "wins"
smb:EnabledServices:_array_index:3 = "wins"
smb:EnabledServices:_array_index:4 = "wins"
smb:EnabledServices:_array_index:5 = "wins"
smb:EnabledServices:_array_index:6 = "wins"
smb:EnabledServices:_array_index:7 = "print"
smb:EnabledServices:_array_index:8 = "wins"
smb:EnabledServices:_array_index:9 = "wins"
smb:EnabledServices:_array_index:10 = "disk"
smb:PasswordServer = ""
smb:AllowNTLM2Auth = yes
smb:MaxClients = 100
smb:ServerRole = "PrimaryDomainController"
smb:AllowGuestAccess = no
smb:guestAccess = yes
smb:AllowKerberosAuth = yes
smb:DOSCodePage = "CP437"