Bug description: Windows Sync sends password modify even if it is
from PassSync originated on AD. The modify updates the pwdLastSet
attribute value to non-zero value. The value 0 indicates the pass-
word must change at next logon on AD.
Fix description: Before sending the password modify, check whether
the current pwdLastSet value is 0 or not. If it is 0 (means the
password must change), reset pwdLastSet value to 0 along with the
password modify. This operation replaces the password on AD, but
the password still must change at next logon.
Note: If "password must change at next logon" on the both DS and AD,
the password needs to be changed by the user on the both servers to
enable it on each.