diff --git a/ChangeLog b/ChangeLog
index 44cc22be5a..39b6b97d01 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+Sat Jan 28 08:18:11 2012  Hiroshi Shirosaki  <h.shirosaki@gmail.com>
+
+	* test/ruby/test_thread.rb
+	  (TestThreadGroup#test_thread_timer_and_interrupt): skip exit status
+	  assertion because we cannot get signal status on Windows.
+
+	* win32/win32.c (CreateChild): create process group to receive the
+	  signal by GenerateConsoleCtrlEvent().
+
+	* win32/win32.c (kill): use CTRL_BREAK_EVENT instead of CTRL_C_EVENT
+	  if a process group is specified. CTRL_C_EVENT signal cannot be
+	  generated for process groups for the specification.
+	  [ruby-dev:45149] [Bug #5812]
+
 Sat Jan 28 07:46:03 2012  Hiroshi Shirosaki  <h.shirosaki@gmail.com>
 
 	* thread_win32.c (rb_w32_wait_events_blocking): use
diff --git a/test/ruby/test_thread.rb b/test/ruby/test_thread.rb
index 0931de5659..6f7d1280bd 100644
--- a/test/ruby/test_thread.rb
+++ b/test/ruby/test_thread.rb
@@ -694,9 +694,14 @@ class TestThreadGroup < Test::Unit::TestCase
     Process.kill(:SIGINT, pid)
     Process.wait(pid)
     s = $?
-    assert_equal([false, true, false],
-                 [s.exited?, s.signaled?, s.stopped?],
-                 "[s.exited?, s.signaled?, s.stopped?]")
+    if /mswin|mingw/ =~ RUBY_PLATFORM
+      # status of signal is not supported on Windows
+      assert_equal(pid, s.pid)
+    else
+      assert_equal([false, true, false],
+                   [s.exited?, s.signaled?, s.stopped?],
+                   "[s.exited?, s.signaled?, s.stopped?]")
+    end
     t1 = Time.now.to_f
     assert_in_delta(t1 - t0, 1, 1)
   end
diff --git a/win32/win32.c b/win32/win32.c
index 7cb1b31df6..9922fa5b14 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -1132,7 +1132,7 @@ CreateChild(const WCHAR *cmd, const WCHAR *prog, SECURITY_ATTRIBUTES *psa,
 	aStartupInfo.hStdError = GetStdHandle(STD_ERROR_HANDLE);
     }
 
-    dwCreationFlags = (NORMAL_PRIORITY_CLASS);
+    dwCreationFlags = (CREATE_NEW_PROCESS_GROUP | NORMAL_PRIORITY_CLASS);
 
     if (lstrlenW(cmd) > 32767) {
 	child->pid = 0;		/* release the slot */
@@ -4094,7 +4094,13 @@ kill(int pid, int sig)
 
       case SIGINT:
 	RUBY_CRITICAL({
-	    if (!GenerateConsoleCtrlEvent(CTRL_C_EVENT, (DWORD)pid)) {
+	    DWORD ctrlEvent = CTRL_C_EVENT;
+	    if (pid != 0) {
+	        /* CTRL+C signal cannot be generated for process groups.
+		 * Instead, we use CTRL+BREAK signal. */
+	        ctrlEvent = CTRL_BREAK_EVENT;
+	    }
+	    if (!GenerateConsoleCtrlEvent(ctrlEvent, (DWORD)pid)) {
 		if ((err = GetLastError()) == 0)
 		    errno = EPERM;
 		else