diff --git a/sphinx/builders/epub.py b/sphinx/builders/epub.py
index 366587b66..28e0ece5b 100644
--- a/sphinx/builders/epub.py
+++ b/sphinx/builders/epub.py
@@ -171,7 +171,7 @@ class EpubBuilder(StandaloneHTMLBuilder):
         name = name.replace('<', '&lt;')
         name = name.replace('>', '&gt;')
         name = name.replace('"', '&quot;')
-        name = name.replace('\'', '&apos;')
+        name = name.replace('\'', '&#39;')
         return name
 
     def get_refnodes(self, doctree, result):
diff --git a/sphinx/writers/html.py b/sphinx/writers/html.py
index 85c653602..613397ea8 100644
--- a/sphinx/writers/html.py
+++ b/sphinx/writers/html.py
@@ -244,6 +244,12 @@ class HTMLTranslator(BaseTranslator):
     def visit_doctest_block(self, node):
         self.visit_literal_block(node)
 
+    # overwritten to add the <div> (for XHTML compliance)
+    def visit_block_quote(self, node):
+        self.body.append(self.starttag(node, 'blockquote') + '<div>')
+    def depart_block_quote(self, node):
+        self.body.append('</div></blockquote>\n')
+
     # overwritten
     def visit_literal(self, node):
         if len(node.children) == 1 and \