samba password doesn't work after last update

[f p]

After last update of Ubuntu, on trying to open a remote system it no longer accepts a password that worked today before the update.

This happens both on the file explorer and gvfs-mount.
It asks for a password for ever and does not accept a valid one.
A remote folder with no password works ok both ways.

Description: Ubuntu 12.04.2 LTS
Release: 12.04

gvfs:
  Instalados: 1.12.1-0ubuntu1.2
  Candidato: 1.12.1-0ubuntu1.2
  Tabla de versión:
 *** 1.12.1-0ubuntu1.2 0
        500 http://cl.archive.ubuntu.com/ubuntu/ precise-updates/main i386 Packages
        100 /var/lib/dpkg/status
     1.12.1-0ubuntu1 0
        500 http://cl.archive.ubuntu.com/ubuntu/ precise/main i386 Packages