diff --git a/mysite/missions/diffpatch/controllers.py b/mysite/missions/diffpatch/controllers.py
index 02bf5ff..fdbd90b 100644
--- a/mysite/missions/diffpatch/controllers.py
+++ b/mysite/missions/diffpatch/controllers.py
@@ -63,6 +63,8 @@ class SingleFilePatch(object):
         if ''.join(the_patch.patch_stream(open(cls.OLD_FILE), the_patch.hunks[0])) == open(cls.NEW_FILE).read():
             # Sweet! Success.
             return True
+        else:
+            raise IncorrectPatch, "\n---------========-------------\n".join([''.join(the_patch.patch_stream(open(cls.OLD_FILE), the_patch.hunks[0])), open(cls.NEW_FILE).read()])
 
         # Okay, at this point, we know the resulting contents are not good.