Remove href from the email text.
{% extends "index.html" %}
{% load i18n %}
{% block centercontent %}
<div class="post">
<div class="title"><h2>{% trans "Register" %}</h2></div>
<div id="search">
<style type="text/css">
ul.errorlist {
margin: 0;
padding: 0;
}
.errorlist li {
color: red;
display: block;
font-size: 10px;
margin: 0 1 3px;
padding: 0px 45px;
}
</style>
<table>
Your account has been created. An activation email will be sent
soon to the email ID with which you registered.<br /><br />
Please visit the link mentioned in the mail to activate your account.
</table>
<script type="text/javascript">
document.getElementById('id_username').focus();
</script>
</div>
{% endblock %}