After investigations, commit the proposed patch by kklimonda presented with the
following introduction :
cm/templates/site/login_form.html template uses a relative url for the form action, which seems to break deployment in the subfolder when trailing slash is missing (the form redirects to the upper folder breaking login). Using {% url login %} (as in the attached patch) instead would fix the issue.
{% extends "site/layout/base.html" %}
{% block content %}
<h1>Test</h1>
<script type="text/javascript">
var xtabs;
$(function() {
xtabs = $("#tabs").tabs();
});
</script>
<div class="demo">
<div id="tabs">
<ul>
<li><a id="0" href="#tabs-0">Nunc tincidunt</a></li>
<li><a id="1" href="{% url test_inner %}">Ajax Tab 1</a></li>
</ul>
<div id="tabs-0">
<p>Proin elit arcu, rutrum commodo, vehicula tempus, commodo a, risus. Curabitur nec arcu. Donec sollicitudin mi sit amet mauris. Nam elementum quam ullamcorper ante. Etiam aliquet massa et lorem. Mauris dapibus lacus auctor risus. Aenean tempor ullamcorper leo. Vivamus sed magna quis ligula eleifend adipiscing. Duis orci. Aliquam sodales tortor vitae ipsum. Aliquam nulla. Duis aliquam molestie erat. Ut et mauris vel pede varius sollicitudin. Sed ut dolor nec orci tincidunt interdum. Phasellus ipsum. Nunc tristique tempus lectus.</p>
</div>
</div>
{% endblock %}