diff --git a/ChangeLog b/ChangeLog
index 1a25eab1ca..e3ad8329d7 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri May 27 08:47:26 2011  Hidetoshi NAGAI  <nagai@ai.kyutech.ac.jp>
+
+	* thread.c (ppoll): typo bug fix.
+
 Fri May 27 08:35:04 2011  Hidetoshi NAGAI  <nagai@ai.kyutech.ac.jp>
 
 	* ext/tk/lib/tk.rb: hang-up at exit before calling Tk.mainloop.
diff --git a/thread.c b/thread.c
index cf7affa424..1614bfe925 100644
--- a/thread.c
+++ b/thread.c
@@ -2759,14 +2759,14 @@ int ppoll(struct pollfd *fds, nfds_t nfds,
 	    timeout_ms = -1;
 	else {
 	    tmp = ts->tv_sec * 1000;
-	    tmp2 = tv->tv_nsec / (1000 * 1000);
+	    tmp2 = ts->tv_nsec / (1000 * 1000);
 	    if (TIMET_MAX - tmp < tmp2)
 		timeout_ms = -1;
 	    else
 		timeout_ms = tmp + tmp2;
 	}
     } else
-	timeout = -1;
+	timeout_ms = -1;
 
     return poll(fds, nfds, timeout_ms);
 }