diff -r d229032dc213 Modules/_randommodule.c
--- a/Modules/_randommodule.c	Tue Apr 17 22:48:06 2012 -0400
+++ b/Modules/_randommodule.c	Thu Apr 19 07:50:30 2012 +0100
@@ -427,8 +427,11 @@
         mt[j] = tmp;
     }
 
-    for (i = 0; i < N; i++)
+    mt[0] = 0x80000000UL; /* MSB is 1; assuring non-zero initial array */
+    for (i = 1; i < N; i++) {
         mt[i] += i+1;
+        mt[i] &= 0xffffffffUL; /* for WORDSIZE > 32 machines */
+    }
 
     self->index = N;
     Py_INCREF(Py_None);