diff --git a/Gemfile b/Gemfile
index dbc00c9..0748532 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,6 +4,7 @@ source 'https://rubygems.org'
 gemspec unless RUBY_ENGINE == 'jruby'
 
 group :development do
+  gem "bigdecimal"
   gem "bundler"
   gem "rake"
   gem "rake-compiler"
diff --git a/ext/date/date_core.c b/ext/date/date_core.c
index 575e0e4..22946d4 100644
--- a/ext/date/date_core.c
+++ b/ext/date/date_core.c
@@ -6920,7 +6920,7 @@ cmp_gen(VALUE self, VALUE other)
     get_d1(self);
 
     if (k_numeric_p(other))
-	return INT2FIX(f_cmp(m_ajd(dat), other));
+	return rb_funcallv(m_ajd(dat), id_cmp, 1, &other);
     else if (k_date_p(other))
 	return INT2FIX(f_cmp(m_ajd(dat), f_ajd(other)));
     return rb_num_coerce_cmp(self, other, id_cmp);
diff --git a/test/date/test_date_arith.rb b/test/date/test_date_arith.rb
index c3633c9..ca9b553 100644
--- a/test/date/test_date_arith.rb
+++ b/test/date/test_date_arith.rb
@@ -97,6 +97,21 @@ def test__compare
 		     DateTime.new(2001,1,17,0,0,0,0,Date::GREGORIAN)))
   end
 
+  def test__compare_nan
+    nans = [Float::NAN]
+    begin
+      require "bigdecimal"
+      nans << BigDecimal("NaN")
+    rescue LoadError
+    end
+    d = Date.new(2000,1,1)
+    nans.each do |nan|
+      assert_nil(d <=> nan)
+      assert_equal(false, d == nan)
+      assert_raise(ArgumentError) { d < nan }
+    end
+  end
+
   def test_prev
     d = Date.new(2000,1,1)
     assert_raise(NoMethodError) do