diff --git a/xsd/atom.rng b/xsd/atom.rng
index ac63ec4fc..f1407fc4d 100644
--- a/xsd/atom.rng
+++ b/xsd/atom.rng
@@ -2,10 +2,9 @@
 <!--
   -*- rnc -*-
   RELAX NG Compact Syntax Grammar for the
-  Atom Format Specification
-  draft-ietf-atompub-format-10
+  Atom Format Specification Version 11
 -->
-<grammar xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:s="http://www.ascc.net/xml/schematron" xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
+<grammar ns="http://www.w3.org/1999/xhtml" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:s="http://www.ascc.net/xml/schematron" xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
   <start>
     <choice>
       <ref name="atomFeed"/>
@@ -354,9 +353,9 @@
     <element name="atom:source">
       <ref name="atomCommonAttributes"/>
       <interleave>
-        <optional>
+        <zeroOrMore>
           <ref name="atomAuthor"/>
-        </optional>
+        </zeroOrMore>
         <zeroOrMore>
           <ref name="atomCategory"/>
         </zeroOrMore>
@@ -570,7 +569,7 @@
   <!-- XHTML -->
   <define name="anyXHTML">
     <element>
-      <nsName ns="http://www.w3.org/1999/xhtml"/>
+      <nsName/>
       <zeroOrMore>
         <choice>
           <attribute>
diff --git a/xsl/common.xsl b/xsl/common.xsl
index 2e413815f..96199eeb2 100644
--- a/xsl/common.xsl
+++ b/xsl/common.xsl
@@ -384,6 +384,14 @@
         </xsl:call-template>, <xsl:call-template name="format-filesize">
          <xsl:with-param name="value" select="@size"/>
       </xsl:call-template>)
+
+      <xsl:if test="$baseurl = '' or $baseurl = '../'">
+	<!-- Include chapters only in XHTML for JS player. ATOM feeds
+	     copy chapters outside <content type="xhtml"/>
+	-->
+	<xsl:copy-of select="sc:chapters"
+		     xmlns:sc="http://podlove.de/simple-chapters"/>
+      </xsl:if>
     </li>
   </xsl:template>