1 files changed, 1 insertions, 1 deletions
diff --git a/src/DotNetOpenAuth.OpenId.Provider/OpenId/Messages/AssociateRequestProviderTools.cs b/src/DotNetOpenAuth.OpenId.Provider/OpenId/Messages/AssociateRequestProviderTools.cs
index 0fb5e98..a03c93f 100644
--- a/src/DotNetOpenAuth.OpenId.Provider/OpenId/Messages/AssociateRequestProviderTools.cs
+++ b/src/DotNetOpenAuth.OpenId.Provider/OpenId/Messages/AssociateRequestProviderTools.cs
@@ -7,11 +7,11 @@
 namespace DotNetOpenAuth.OpenId.Messages {
 	using System;
 	using System.Collections.Generic;
-	using System.Diagnostics.Contracts;
 	using System.Linq;
 	using System.Text;
 	using DotNetOpenAuth.Messaging;
 	using DotNetOpenAuth.OpenId.Provider;
+	using Validation;
 
 	/// <summary>
 	/// OpenID Provider tools for receiving association requests.