diff --git a/ChangeLog b/ChangeLog
index f79f0995b6..33b796e2ca 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Mon Dec 31 22:53:29 2007  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* thread_pthread.c (native_sleep): timespec tv_sec may overflow on
+	  some platform.  a patch from zunda <zunda616e AT yahoo.co.jp> in 
+	  [ruby-dev:32904].
+
 Mon Dec 31 19:35:20 2007  Tanaka Akira  <akr@fsij.org>
 
 	* string.c (IS_7BIT): removed.
diff --git a/thread_pthread.c b/thread_pthread.c
index daeca964a7..962215b1a1 100644
--- a/thread_pthread.c
+++ b/thread_pthread.c
@@ -432,7 +432,7 @@ native_sleep(rb_thread_t *th, struct timeval *tv)
 	    thread_debug("native_sleep: interrupted before sleep\n");
 	}
 	else {
-	    if (tv == 0) {
+	    if (tv == 0 || ts.tv_sec < tvn.tv_sec /* overflow */ ) {
 		thread_debug("native_sleep: pthread_cond_wait start\n");
 		pthread_cond_wait(&th->native_thread_data.sleep_cond,
 				  &th->interrupt_lock);