User is not working as expected

gistfile1.txt

# SNIPPET FROM MY MODULE #
          user { 'myuser':
            require    => Package["bla"],
            name       => 'myuser',
            password   => '$6$OszcHZZq$/PLagjQvt3jG/zfM1S/vU5vF4dMEXzdrPcc2.Iih01TxhN8004sQIKJpXQd5K7JySWIHSGwTHnY0mKrqFQd3H1',
            ensure     => present,
            home       => '/opt/myuser',
            comment    => 'myuser agent user (managed by puppet)',
            managehome => true,
            shell      => '/bin/bash',
            system     => true,
            uid        => 123,
            gid        => 123,
          }
# SNIPPET FROM MY MODULE #

# On a working ubuntu 12.04 server:
# $ grep myuser /etc/shadow
# myuser:$6$OszcHZZq$/PLagjQvt3jG/zfM1S/vU5vF4dMEXzdrPcc2.Iih01TxhN8004sQIKJpXQd5K7JySWIHSGwTHnY0mKrqFQd3H1:16196::::::
#
# My ubuntu 12.04 server with issues:
# $ grep myuser /etc/shadow
# myuser:!:16196::::::