diff --git a/src/calibre/ebooks/oeb/display/webview.py b/src/calibre/ebooks/oeb/display/webview.py
index a186044fe5..87a27d73e1 100644
--- a/src/calibre/ebooks/oeb/display/webview.py
+++ b/src/calibre/ebooks/oeb/display/webview.py
@@ -31,7 +31,7 @@ def self_closing_sub(match):
     return '<%s%s></%s>'%(match.group(1), match.group(2), match.group(1))
 
 def load_html(path, view, codec='utf-8', mime_type=None,
-        pre_load_callback=lambda x:None, path_is_html=False,
+              pre_load_callback=lambda x:None, path_is_html=False,
               force_as_html=False):
     from PyQt4.Qt import QUrl, QByteArray
     if mime_type is None:
@@ -45,7 +45,7 @@ def load_html(path, view, codec='utf-8', mime_type=None,
             html = f.read().decode(codec, 'replace')
 
     html = EntityDeclarationProcessor(html).processed_html
-    self_closing_pat = re.compile(r'<\s*([A-Za-z1-6]+)([^>]*)/\s*>')
+    self_closing_pat = re.compile(r'<\s*([:A-Za-z1-6]+)([^>]*)/\s*>')
     html = self_closing_pat.sub(self_closing_sub, html)
 
     loading_url = QUrl.fromLocalFile(path)
diff --git a/src/calibre/gui2/viewer/documentview.py b/src/calibre/gui2/viewer/documentview.py
index 7df171a404..1878b5e760 100644
--- a/src/calibre/gui2/viewer/documentview.py
+++ b/src/calibre/gui2/viewer/documentview.py
@@ -790,8 +790,7 @@ class DocumentView(QWebView): # {{{
                 self.manager.load_started()
 
         load_html(path, self, codec=getattr(path, 'encoding', 'utf-8'), mime_type=getattr(path,
-            'mime_type', 'text/html'), pre_load_callback=callback,
-                  force_as_html=True)
+            'mime_type', 'text/html'), pre_load_callback=callback)
         entries = set()
         for ie in getattr(path, 'index_entries', []):
             if ie.start_anchor: