Index: Python/pythonrun.c
===================================================================
--- Python/pythonrun.c	(revision 76915)
+++ Python/pythonrun.c	(working copy)
@@ -864,6 +864,11 @@
 			*errors = '\0';
 			errors++;
 		}
+		/* Not a fatal error if codec isn't available */
+		if (!_PyCodec_Lookup(encoding)) {
+			PyErr_Clear();
+			encoding = NULL;
+		}
 	}
 
 	/* Set sys.stdin */