diff --git a/ChangeLog b/ChangeLog
index ca79ffbb17..5c3f42d8c4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu May  1 16:10:21 2008  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* hash.c (env_delete_if): return enumerator if no block given.
+	  [ruby-dev:34554]
+
 Wed Apr 30 21:36:40 2008  Masatoshi SEKI  <m_seki@mva.biglobe.ne.jp>
 
 	* lib/erb.rb (url_encode): [ruby-dev:34497] ERB::Util#url_encode
diff --git a/hash.c b/hash.c
index 89c470f9e4..8d3567e315 100644
--- a/hash.c
+++ b/hash.c
@@ -2184,6 +2184,7 @@ env_reject_bang(VALUE ehash)
 static VALUE
 env_delete_if(VALUE ehash)
 {
+    RETURN_ENUMERATOR(ehash, 0, 0);
     env_reject_bang(ehash);
     return envtbl;
 }