Magento 1.3.X environment won’t run on PHP 5.3.X due to functions being deprecated. No sweat, there is a quick fix here!

So, you still have your website in Magento 1.3.X because it has too many customizations and you can’t upgrade, but you decide to upgrade to PHP 5.3.X due to the annoyingness from PCI with the compliance changing every hour and when you are going to check your website… a strange error appears due to some PHP functions being deprecated? Yes, it happens to many of us, but fortunately, here is a solution!
So, when you try to run your website, you get something like this:

Unknown error (8192): Function split() is deprecated in   /app/code/core/Mage/Admin/Model/User.php on line 374 Trace: #0 [internal function]: mageCoreErrorHandler(8192, ‘Function split(…’, ‘ /app/code/core/Mage/…’, 374, Array) #1   /app/code/core/Mage/Admin/Model/User.php(374): split() #2   /app/code/core/Mage/Adminhtml/controllers/IndexController.php(42): Mage_Admin_Model_User->getStartupPageUrl() #3   /app/code/core/Mage/Core/Controller/Varien/Action.php(376): Mage_Adminhtml_IndexController->indexAction() #4   /app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(248): Mage_Core_Controller_Varien_Action->dispatch(’index’) #5   /app/code/core/Mage/Core/Controller/Varien/Front.php(158): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http)) #6   /app/Mage.php(459): Mage_Core_Controller_Varien_Front->dispatch() #7   /index.php(65): Mage::run() #8 {main}

Well, basically what’s happening is that some functions go deprecated from PHP 5.2.X to 5.3.X and these are present in Magento 1.3.X (but not in Magento 1.4.X).
The solution is a quick fix that involves just 3 files:
Open the file lib/Varien/Object.php, and do the following change:
Look for the line:

public function ___toString(array $arrAttributes = array(), $valueSeparator=’,’)

Change it to:

public function __invoke(array $arrAttributes = array(), $valueSeparator=’,’)

Now, go to the file: app\code\core\Mage\Core\Controller\Request\Http.php and change:
Look for the line:

$host = split(‘:’, $_SERVER['HTTP_HOST']);

Change it to:

$host = explode(‘:’, $_SERVER['HTTP_HOST']);

Also, go to app\code\core\Mage\Catalog\Model\Category\Attribute\Backend\Sortby.php and change:
Look for the line:

$object->setData($attributeCode, split(‘,’, $data));

Replace With:

$object->setData($attributeCode, explode(‘,’, $data));

Finally, open the file: app\code\core\Mage\Admin\Model\User.php and change:
Look for the line:

$nodePath = ‘adminhtml/menu/’ . join(‘/children/’, split(‘/’, $startupPage)) . ‘/action’;

Replace With:

$nodePath = ‘adminhtml/menu/’ . join(‘/children/’, explode(‘/’, $startupPage)) . ‘/action’;

That’s it, you Magento environment should run again.