diff --git a/ChangeLog b/ChangeLog
index fb7026e155..21f6c970d6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jul  3 23:41:30 2003  Tanaka Akira  <akr@m17n.org>
+
+	* lib/timeout.rb: add optional exception argument for compatibility
+	  function.
+
 Thu Jul  3 14:22:46 2003  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* array.c (rb_values_at): extract common procedure from
diff --git a/lib/timeout.rb b/lib/timeout.rb
index 00e60aff8c..f5c4e3cbf0 100644
--- a/lib/timeout.rb
+++ b/lib/timeout.rb
@@ -51,8 +51,8 @@ module Timeout
 end
 
 # compatible
-def timeout(n, &block)
-  Timeout::timeout(n, &block)
+def timeout(n, e=Timeout::Error, &block)
+  Timeout::timeout(n, e, &block)
 end
 TimeoutError = Timeout::Error
 
@@ -60,6 +60,9 @@ if __FILE__ == $0
   p timeout(5) {
     45
   }
+  p timeout(5, TimeoutError) {
+    45
+  }
   p timeout(5) {
     loop {
       p 10