diff --git a/lib/rb/spec/union_spec.rb b/lib/rb/spec/union_spec.rb
index 4835288..07a3f94 100644
--- a/lib/rb/spec/union_spec.rb
+++ b/lib/rb/spec/union_spec.rb
@@ -141,5 +141,11 @@
       swu2.read(proto)
       swu2.should == swu
     end
+    
+    it "should support old style constructor" do
+      union = My_union.new(:integer32 => 26)
+      union.get_set_field.should == :integer32
+      union.get_value.should == 26
+    end
   end
 end