Jekyll Template for Atom, RSS feed. Template leaves HTML entities like — intact in XML + XSLT

feed.xml

---
layout: nil
title : Atom Feed
---
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE xsl:stylesheet [<!ENTITY mdash "&#x2014;">]>
<feed xmlns="http://www.w3.org/2005/Atom">
  <title type="text" xml:lang="en">{{site.name}}</title>
  <link type="application/atom+xml" href="{{site.url}}/feed.xml" rel="self"/>
  <link type="text/html" href="{{site.url}}" rel="alternate"/>
  <updated>{{ site.time | date_to_xmlschema }}</updated>
  <id>{{site.url}}/all_feed</id>
  <author>
    <name>{{site.owner.name}}</name>
  </author>

  {% for post in site.posts limit:20 %}
  <entry>
    <title>{{ post.title }}</title>
    <link href="{{site.url}}{{ post.url }}"/>
    <updated>{{ post.date | date_to_xmlschema }}</updated>
    <id>{{site.url}}{{ post.id }}</id>
    <content type="html">{{ post.content | xml_escape }}</content>
  </entry>
  {% endfor %}
</feed>