diff -r ed091424f230 Lib/idlelib/EditorWindow.py
--- a/Lib/idlelib/EditorWindow.py	Sat Nov 03 17:51:25 2012 +0200
+++ b/Lib/idlelib/EditorWindow.py	Sat Nov 17 11:57:33 2012 -0600
@@ -1614,7 +1614,7 @@
                 tokens = _tokenize.generate_tokens(self.readline)
                 for token in tokens:
                     self.tokeneater(*token)
-            except _tokenize.TokenError:
+            except (_tokenize.TokenError, IndentationError, SyntaxError):
                 # since we cut off the tokenizer early, we can trigger
                 # spurious errors
                 pass