diff --git a/js/validator.js b/js/validator.js
index f59a6b7..fd57bbf 100644
--- a/js/validator.js
+++ b/js/validator.js
@@ -140,7 +140,7 @@
     }
 
     $.each(Validator.VALIDATORS, $.proxy(function (key, validator) {
-      if (($el.data(key) || key == 'native') && !validator.call(this, $el)) {
+      if ((typeof $el.data(key) !== 'undefined' || key == 'native') && !validator.call(this, $el)) {
         var error = getErrorMessage(key)
         !~errors.indexOf(error) && errors.push(error)
       }