diff --git a/source/Plugins/AyaNova.Plugin.V8/util.cs b/source/Plugins/AyaNova.Plugin.V8/util.cs
index 0a28f0f..fa63b07 100644
--- a/source/Plugins/AyaNova.Plugin.V8/util.cs
+++ b/source/Plugins/AyaNova.Plugin.V8/util.cs
@@ -342,7 +342,7 @@ namespace AyaNova.PlugIn.V8
 
         ///////////////////////////////
         // v7 to v8 Date conversion
-        //
+        //NOTE: ensure null for empty date 
         //
         public static string DateToV8(object o, bool neverEmpty = false) { return DateToV8(o.ToString(), neverEmpty); }
         public static string DateToV8(string s, bool neverEmpty = false)
@@ -355,7 +355,7 @@ namespace AyaNova.PlugIn.V8
                 }
                 else
                 {
-                    return string.Empty;
+                    return null;
                 }
             }
 
@@ -366,7 +366,7 @@ namespace AyaNova.PlugIn.V8
             //couldn't be parsed
             if (neverEmpty)
                 return DateTime.UtcNow.ToString("o");
-            return string.Empty;
+            return null;
         }
 
         ///////////////////////////////