With the addition of better PAM support in Samba 2.2, 
    this parameter, it is possible to use PAM's password change control 
    flag for Samba.  If enabled, then PAM will be used for password
    changes when requested by an SMB client instead of the program listed in 
    . 
    It should be possible to enable this without changing your 
     parameter for most setups.
no