diff --git a/ChangeLog b/ChangeLog
index dc3debf356..5ae31b5028 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Tue Jun  4 15:30:00 2013  Kenta Murata  <mrkn@cookpad.com>
+
+	* ext/bigdecimal/lib/bigdecimal/util.rb (Float#to_d): fix the number
+	  of figures.  Patch by Vipul A M <vipulnsward@gmail.com>.
+	  https://github.com/ruby/ruby/pull/323  fix GH-323
+
+	* test/bigdecimal/test_bigdecimal_util.rb: fix for the above change.
+
 Tue Jun  4 00:44:27 2013  Kazuhiro NISHIYAMA  <zn@mbf.nifty.com>
 
 	* test/fileutils/test_fileutils.rb (TestFileUtils#test_mkdir): add
diff --git a/ext/bigdecimal/lib/bigdecimal/util.rb b/ext/bigdecimal/lib/bigdecimal/util.rb
index b27e64c511..bd02ef427c 100644
--- a/ext/bigdecimal/lib/bigdecimal/util.rb
+++ b/ext/bigdecimal/lib/bigdecimal/util.rb
@@ -28,7 +28,7 @@ class Float < Numeric
   #     # => #<BigDecimal:1dc69e0,'0.5E0',9(18)>
   #
   def to_d(precision=nil)
-    BigDecimal(self, precision || Float::DIG+1)
+    BigDecimal(self, precision || Float::DIG)
   end
 end
 
diff --git a/test/bigdecimal/test_bigdecimal_util.rb b/test/bigdecimal/test_bigdecimal_util.rb
index 72342b922f..9a5d504abd 100644
--- a/test/bigdecimal/test_bigdecimal_util.rb
+++ b/test/bigdecimal/test_bigdecimal_util.rb
@@ -14,9 +14,10 @@ class TestBigDecimalUtil < Test::Unit::TestCase
   end
 
   def test_Float_to_d_without_precision
-    delta = 1.0/10**(Float::DIG + 1)
-    assert_in_delta(BigDecimal(0.5, Float::DIG+1), 0.5.to_d, delta)
-    assert_in_delta(BigDecimal(355.0/113.0, Float::DIG+1), (355.0/113.0).to_d, delta)
+    delta = 1.0/10**(Float::DIG)
+    assert_in_delta(BigDecimal(0.5, Float::DIG), 0.5.to_d, delta)
+    assert_in_delta(BigDecimal(355.0/113.0, Float::DIG), (355.0/113.0).to_d, delta)
+    assert_equal(9.05.to_d.to_s('F'), "9.05")
   end
 
   def test_Float_to_d_with_precision