diff -r 5a9171e70573 Lib/pydoc.py
--- a/Lib/pydoc.py	Fri Jan 17 15:24:18 2014 -0600
+++ b/Lib/pydoc.py	Sat Jan 18 23:05:00 2014 -0600
@@ -925,7 +925,10 @@
                 anchor, name, reallink)
         argspec = None
         if inspect.isfunction(object) or inspect.isbuiltin(object):
-            signature = inspect.signature(object)
+            try:
+                signature = inspect.signature(object)
+            except ValueError:
+                signature = None
             if signature:
                 argspec = str(signature)
                 if realname == '<lambda>':
@@ -1320,7 +1323,10 @@
             title = self.bold(name) + ' = ' + realname
         argspec = None
         if inspect.isfunction(object) or inspect.isbuiltin(object):
-            signature = inspect.signature(object)
+            try:
+                signature = inspect.signature(object)
+            except ValueError:
+                signature = None
             if signature:
                 argspec = str(signature)
                 if realname == '<lambda>':