diff --git a/app/code/core/Mage/Sales/Model/Quote/Address.php b/app/code/core/Mage/Sales/Model/Quote/Address.php
index b3ca22dc0b2..7acfd689fc0 100644
--- a/app/code/core/Mage/Sales/Model/Quote/Address.php
+++ b/app/code/core/Mage/Sales/Model/Quote/Address.php
@@ -1167,8 +1167,12 @@ public function validateMinimumAmount()
      */
     public function getAppliedTaxes()
     {
+        $tax = $this->getData('applied_taxes');
+        if (empty($tax)) {
+            return [];
+        }
         try {
-            $return = Mage::helper('core/unserializeArray')->unserialize($this->getData('applied_taxes'));
+            $return = Mage::helper('core/unserializeArray')->unserialize($tax);
         } catch (Exception $e) {
             $return = [];
         }