diff --git a/app/code/core/Mage/Core/Model/Config.php b/app/code/core/Mage/Core/Model/Config.php
index fa676659c4e..13a5dd9e355 100644
--- a/app/code/core/Mage/Core/Model/Config.php
+++ b/app/code/core/Mage/Core/Model/Config.php
@@ -1386,7 +1386,7 @@ public function getModelClassName($modelClass)
     public function getModelInstance($modelClass = '', $constructArguments = array())
     {
         $className = $this->getModelClassName($modelClass);
-        if (class_exists($className)) {
+        if (!empty($className) && class_exists($className)) {
             Varien_Profiler::start('CORE::create_object_of::'.$className);
             $obj = new $className($constructArguments);
             Varien_Profiler::stop('CORE::create_object_of::'.$className);