diff --git a/lib/document_stores/googledatastore.js b/lib/document_stores/googledatastore.js
index 22ffe5d..97385f1 100644
--- a/lib/document_stores/googledatastore.js
+++ b/lib/document_stores/googledatastore.js
@@ -15,7 +15,7 @@ class GoogleDatastoreDocumentStore {
   // Save file in a key
   set(key, data, callback, skipExpire) {
     var now = new Date();
-    var expireTime = skipExpire ? null : new Date(now.getTime() + this.expire * 1000);
+    var expireTime = skipExpire ? new Date(null) : new Date(now.getTime() + this.expire * 1000);
     
     var taskKey = this.datastore.key([this.kind, key])
     var task = {
@@ -52,7 +52,7 @@ class GoogleDatastoreDocumentStore {
       }
       else {
         // check for expiry
-        if (entity[0]["expiration"] != null && entity[0]["expiration"] < new Date()) {
+        if (entity[0]["expiration"] != new Date(null) && entity[0]["expiration"] < new Date()) {
           winston.info("document expired", {key: key});
           callback(false);
         }