Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/Assemblers/DtoAssembler.cs
===================================================================
diff -u -r4540 -r5774
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/Assemblers/DtoAssembler.cs	(.../DtoAssembler.cs)	(revision 4540)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/Assemblers/DtoAssembler.cs	(.../DtoAssembler.cs)	(revision 5774)
@@ -233,8 +233,9 @@
     /// <param name="domainObj">The domain object</param>
     /// <returns>An XElement instance</returns>
     public override XElement CreateDataTransferObject(TDomainObject domainObj)
+        
     {
-        if (domainObj == null)
+        if (!typeof(TDomainObject).IsValueType && (domainObj == null))
         {
             return null;
         }