diff --git a/ChangeLog b/ChangeLog
index 2d02e95834..629e11c902 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Aug 30 01:15:31 2009  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* ext/zlib/zlib.c (gzfile_read_all): use gzfile_newstr;
+	  set and convert its encoding. [ruby-dev:38304]
+
 Sat Aug 29 20:40:02 2009  Yuki Sonoda (Yugui)  <yugui@yugui.jp>
 
 	* vm_eval.c (rb_call0): gets rid of checking method cache twice.
diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index 288b13b728..8f23bcff21 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -2202,7 +2202,7 @@ gzfile_read_all(struct gzfile *gz)
     dst = zstream_detach_buffer(&gz->z);
     gzfile_calc_crc(gz, dst);
     OBJ_TAINT(dst);
-    return dst;
+    return gzfile_newstr(gz, dst);
 }
 
 static VALUE
diff --git a/test/zlib/test_zlib.rb b/test/zlib/test_zlib.rb
index aa3059d5b1..abb3ea32b3 100644
--- a/test/zlib/test_zlib.rb
+++ b/test/zlib/test_zlib.rb
@@ -470,10 +470,12 @@ if defined? Zlib
     def test_read
       t = Tempfile.new("test_zlib_gzip_reader")
       t.close
-      Zlib::GzipWriter.open(t.path) {|gz| gz.print("foobar") }
+      str = "\u3042\u3044\u3046"
+      Zlib::GzipWriter.open(t.path) {|gz| gz.print(str) }
 
-      f = Zlib::GzipReader.open(t.path)
+      f = Zlib::GzipReader.open(t.path, encoding: "UTF-8")
       assert_raise(ArgumentError) { f.read(-1) }
+      assert_equal(str, f.read)
     end
 
     def test_readpartial