diff --git a/ChangeLog b/ChangeLog
index 6491708acc..2f54f1d050 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Fri Nov 30 16:42:50 2007  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* enum.c (enum_take_while): returns Enumerator if no block given.
+
+	* enum.c (enum_drop_while): ditto.
+
 Thu Nov 29 16:59:10 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* parse.y (stmt): remove unnecessary NODE_BEGIN.  [ruby-core:13814]
diff --git a/enum.c b/enum.c
index b778bfea84..4196802de9 100644
--- a/enum.c
+++ b/enum.c
@@ -1451,6 +1451,7 @@ enum_take_while(VALUE obj)
 {
     VALUE ary;
 
+    RETURN_ENUMERATOR(obj, 0, 0);
     ary = rb_ary_new();
     rb_block_call(obj, id_each, 0, 0, take_while_i, (VALUE)&ary);
     return ary;
@@ -1522,6 +1523,7 @@ enum_drop_while(VALUE obj)
 {
     VALUE args[2];
 
+    RETURN_ENUMERATOR(obj, 0, 0);
     args[0] = rb_ary_new();
     args[1] = Qfalse;
     rb_block_call(obj, id_each, 0, 0, drop_while_i, (VALUE)args);