mysphinxext.py: add support for newer versions of sphinx.

 this is a patch by Oerjan Persson from the gevent debian package. Thanks.

doc/mysphinxext.py

@@ -18,8 +18,12 @@ def missing_reference(app, env, node, contnode):
 
     type = node['reftype']
     target = node['reftarget']
-    modname = node['modname']
-    classname = node['classname']
+    if node.has_key('py:module'):
+        modname = node['py:module']
+        classname = node['py:class']
+    else:
+        modname = node['modname']
+        classname = node['classname']
 
     if modname and classname:
         return
@@ -28,7 +32,8 @@ def missing_reference(app, env, node, contnode):
         newnode = nodes.reference('', '')
         newnode['refuri'] = refuri
         newnode['reftitle'] = reftitle
-        newnode['class'] = 'external-xref'
+        newnode['py:class'] = 'external-xref'
+        newnode['classname'] = 'external-xref'
         newnode.append(contnode)
         msg = 'Resolved missing-reference: :%5s:`%s` -> %s' % (type, target, refuri)
         if noisy >= 1 or msg not in message_cache: