diff --git a/test/Spring/Spring.Http.Tests/Spring.Http.Tests.2008.csproj b/test/Spring/Spring.Http.Tests/Spring.Http.Tests.2008.csproj
index f9237789..7b9892f7 100644
--- a/test/Spring/Spring.Http.Tests/Spring.Http.Tests.2008.csproj
+++ b/test/Spring/Spring.Http.Tests/Spring.Http.Tests.2008.csproj
@@ -87,6 +87,9 @@
     <Reference Include="System">
       <Name>System</Name>
     </Reference>
+    <Reference Include="System.Runtime.Serialization">
+      <RequiredTargetFramework>3.0</RequiredTargetFramework>
+    </Reference>
     <Reference Include="System.XML" />
   </ItemGroup>
   <ItemGroup>