make django tests working again, from ymh, see http://www.iri.centrepompidou.fr/dev/hg/comt/rev/e103299bccc0
{% extends "site/layout/base.html" %}
{% load i18n %}
{% block content %}
<h1>500: {% blocktrans %}Server Error{% endblocktrans %}</h1>
{% blocktrans %}An error has occurred.{% endblocktrans %}
{% endblock %}