Comment 26 for bug 1257186

As Thomas (reusch) suggest in #14 :
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Fix:
run "pam-auth-update" and remove "SMB password synchronization".
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This isn't a security issue, simply you must remember that your samba password may not match your system password.
In an enterprise enviroment, if ubuntu is used as samba server, i bet it use kerberos tickets to verify the users identity throught domain controller or alternative ldap infrastructure.