diff --git a/ChangeLog b/ChangeLog
index 67b7dda90e..f2b4e1c629 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Mon Mar 15 11:49:48 2010  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* random.c (rb_reset_random_seed): set seed in this.
+	  [ruby-core:28655]
+
 Mon Mar 15 10:26:02 2010  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* ext/nkf/nkf-utf8/nkf.c: import latest nkf. [master 9306cb0]
diff --git a/random.c b/random.c
index bf78e5049e..d36853f6b3 100644
--- a/random.c
+++ b/random.c
@@ -223,16 +223,34 @@ struct Random {
 
 static struct Random default_rand;
 
+static VALUE rand_init(struct MT *mt, VALUE vseed);
+static VALUE random_seed(void);
+
+static void
+default_rand_init(void)
+{
+    rb_random_t *r = &default_rand.rnd;
+    r->seed = rand_init(&r->mt, random_seed());
+}
+
 unsigned int
 rb_genrand_int32(void)
 {
-    return genrand_int32(&default_rand.rnd.mt);
+    struct MT *mt = &default_rand.rnd.mt;
+    if (!genrand_initialized(mt)) {
+	default_rand_init();
+    }
+    return genrand_int32(mt);
 }
 
 double
 rb_genrand_real(void)
 {
-    return genrand_real(&default_rand.rnd.mt);
+    struct MT *mt = &default_rand.rnd.mt;
+    if (!genrand_initialized(mt)) {
+	default_rand_init();
+    }
+    return genrand_real(mt);
 }
 
 #define BDIGITS(x) (RBIGNUM_DIGITS(x))
@@ -303,8 +321,6 @@ VALUE rb_cRandom;
 #define id_minus '-'
 #define id_plus  '+'
 
-static VALUE random_seed(void);
-
 /* :nodoc: */
 static void
 random_mark(void *ptr)
@@ -831,7 +847,7 @@ rb_rand_internal(unsigned long i)
 {
     struct MT *mt = &default_rand.rnd.mt;
     if (!genrand_initialized(mt)) {
-	rand_init(mt, random_seed());
+	default_rand_init();
     }
     return limited_rand(mt, i);
 }
@@ -1111,7 +1127,7 @@ rb_f_rand(int argc, VALUE *argv, VALUE obj)
     struct MT *mt = &default_rand.rnd.mt;
 
     if (!genrand_initialized(mt)) {
-	rand_init(mt, random_seed());
+	default_rand_init();
     }
     if (argc == 0) goto zero_arg;
     rb_scan_args(argc, argv, "01", &vmax);
diff --git a/test/ruby/test_rand.rb b/test/ruby/test_rand.rb
index b6563954cf..97ac8147bd 100644
--- a/test/ruby/test_rand.rb
+++ b/test/ruby/test_rand.rb
@@ -387,4 +387,14 @@ END
     r2.rand(0x100)
     assert(r1 == r2)
   end
+
+  def test_fork_shuffle
+    pid = fork do
+        (1..10).to_a.shuffle
+        raise 'default seed is not set' if srand == 0
+    end
+    p2, st = Process.waitpid2(pid)
+    assert(st.success?)
+  rescue NotImplementedError, ArgumentError
+  end
 end