Unwrap TargetInvocationException

Author: bahusoid

src/NHibernate/Impl/ExpressionProcessor.cs

@@ -273,8 +273,14 @@ public static object FindValue(Expression expression)
 			}
 
 			var valueExpression = Expression.Lambda(expression).Compile();
-			object value = valueExpression.DynamicInvoke();
-			return value;
+			try
+			{
+				return valueExpression.DynamicInvoke();
+			}
+			catch (TargetInvocationException ex)
+			{
+				throw ReflectHelper.UnwrapTargetInvocationException(ex);
+			}
 		}
 
 		/// <summary>