diff --git a/Include/longobject.h b/Include/longobject.h
index 46105ae..89f2aa3 100644
--- a/Include/longobject.h
+++ b/Include/longobject.h
@@ -53,9 +53,28 @@
 extern DL_IMPORT(void *) PyLong_AsVoidPtr Py_PROTO((PyObject *));
 
 #ifdef HAVE_LONG_LONG
+
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+
+/* Hopefully this is portable... */
+#ifndef LONG_MAX
+#define LONG_MAX 2147483647L
+#endif
+#ifndef ULONG_MAX
+#define ULONG_MAX 4294967295U
+#endif
+#ifndef LONGLONG_MAX
+#define LONGLONG_MAX 9223372036854775807LL
+#endif
+#ifndef ULONGLONG_MAX
+#define ULONGLONG_MAX 0xffffffffffffffffULL
+#endif
 #ifndef LONG_LONG
 #define LONG_LONG long long
 #endif
+
 extern DL_IMPORT(PyObject *) PyLong_FromLongLong Py_PROTO((LONG_LONG));
 extern DL_IMPORT(PyObject *) PyLong_FromUnsignedLongLong Py_PROTO((unsigned LONG_LONG));
 extern DL_IMPORT(LONG_LONG) PyLong_AsLongLong Py_PROTO((PyObject *));