Use strerror on the mac if using MSL (Jack).

Python/errors.c

@@ -38,15 +38,9 @@ PERFORMANCE OF THIS SOFTWARE.
 #endif
 
 #ifdef macintosh
-#ifndef __MSL__
-/* Replace strerror with a Mac specific routine.
-   XXX PROBLEM: some positive errors have a meaning for MacOS,
-   but some library routines set Unix error numbers...
-*/
 extern char *PyMac_StrError Py_PROTO((int));
 #undef strerror
 #define strerror PyMac_StrError
-#endif
 #endif /* macintosh */
 
 #ifndef __STDC__