symposion_app/symposion/templates/emails/speaker_no_profile/message.html

{% load url from future %}
<p>{{ proposal.speaker.name }} attached you as an additional speaker to a
    talk proposal for {{ current_site.name }} entitled "{{ proposal.title }}".</p>

<p>Go to</p>

<p><a href="http://{{ current_site }}{% url 'speaker_create_token' token %}">http://{{ current_site }}{% url 'speaker_create_token' token %}</a></p>

<p>to confirm and fill out your speaker profile.</p>