#2864 change_pass-3.1-1.4.0 plugin issue with double poppassd result code

[anq4]

Hello.
change_pass-3.1-1.4.0 plugin has an issue poppassd returning a double result, like un the following case coming from poppassd-1.8.9 when a soft error is fisrt returned for a weak password, that is indeed still changed.
The interface returns a change error, and the user doesn't know that the password was changed, tries again and receives a different error, and chaos results

Connected to 0.
Escape character is '^]'.
200 poppassd
user pippo
200 Your password please
pass whatever
200 Your new password please
newpass pippone
500 Server error
200 Password changed

This is probably the result of this happening behind on the system, first a warning and then success:

-passwd pippo
Changing password for user pippo.
New password:
BAD PASSWORD: The password contains the user name in some form
Retype new password:
passwd: all authentication tokens updated successfully.