[Samba] Ephimeral wins registraton of WinNTs.

[Marisabel]

Hi, 
we are having a problem for registering names for Win NT servers.
Sometimes they appear in the wins.dat file, but they disappear after a time.
This causes that the server rejects user logins.
Can you tell me with wich version can I solve that?. Please tell me if you need 
further information. 
The version is previous to the 3.X. Do you have any information regarding 
versions?
Best regards,
Marisabel.