Index: source
===================================================================
--- source	(revision 1728)
+++ source	(revision 1729)
@@ -578,7 +578,9 @@
     <p class="note">It is possible for <code
     title="attr-xml-base">xml:base</code> attributes to be present
     even in HTML fragments, as such attributes can be added
-    dynamically using script.</p>
+    dynamically using script. (Such scripts would not be conforming,
+    however, as <code title="attr-xml-base">xml:base</code> attributes
+    as not allowed in <span>HTML documents</span>.)</p>
 
    </dd>
 
@@ -5359,6 +5361,18 @@
   content attribute.</p>
 
 
+  <h4>The <dfn title="attr-xml-base"><code>xml:base</code></dfn>
+  attribute (XML only)</h4>
+
+  <p>The <code title="attr-xml-base">xml:base</code> attribute is
+  defined in XML Base. <a href="#refsXMLBASE">[XMLBASE]</a></p>
+
+  <p>The <code title="attr-xml-base">xml:base</code> attribute may be
+  used on elements of <span>XML documents</span>.  Authors must not
+  use the <code title="attr-xml-base">xml:base</code> attribute in
+  <span>HTML documents</span>.</p>
+
+
   <h4>The <dfn title="attr-dir"><code>dir</code></dfn> attribute</h4>
 
   <p>The <code title="attr-dir">dir</code> attribute specifies the