Index: Lib/traceback.py
===================================================================
--- Lib/traceback.py	(révision 80751)
+++ Lib/traceback.py	(copie de travail)
@@ -210,8 +210,13 @@
 
 def _some_str(value):
     try:
+        value = unicode(value)
+        value = value.encode("ascii", "backslashreplace")
+    except Exception:
+        pass
+    try:
         return str(value)
-    except:
+    except Exception:
         return '<unprintable %s object>' % type(value).__name__