i receive this error message beim trying to get to System> Configuration> Catalog > catalog

i have magento Magento Version 1.6.2.0

There has been an error processing your request
Invalid config field backend model: catalog/system_config_backend_catalog_product_flat

Trace:

0 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Adminhtml/Block/System/Config/Form.php(320): Mage::throwException(‘Invalid config …’)

1 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Adminhtml/Block/System/Config/Form.php(210): Mage_Adminhtml_Block_System_Config_Form->initFields(Object(Varien_Data_Form_Element_Fieldset), Object(Mage_Core_Model_Config_Element), Object(Mage_Core_Model_Config_Element))

2 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Adminhtml/Block/System/Config/Edit.php(92): Mage_Adminhtml_Block_System_Config_Form->initForm()

3 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Adminhtml/controllers/System/ConfigController.php(102): Mage_Adminhtml_Block_System_Config_Edit->initForm()

4 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Core/Controller/Varien/Action.php(420): Mage_Adminhtml_System_ConfigController->editAction()

5 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(254): Mage_Core_Controller_Varien_Action->dispatch(‘edit’)

6 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Core/Controller/Varien/Front.php(176): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))

7 /var/www/web69/html/hifi-galerie-hamburg.de/app/code/core/Mage/Core/Model/App.php(349): Mage_Core_Controller_Varien_Front->dispatch()

8 /var/www/web69/html/hifi-galerie-hamburg.de/app/Mage.php(640): Mage_Core_Model_App->run(Array)

9 /var/www/web69/html/hifi-galerie-hamburg.de/index.php(80): Mage::run(”, ‘store’)

10 {main}

Error log record number: 937832478554

any help?

please..