Why do controller action predispatch events not fire if the controller is rewritten? Here is a snippet of store/app/code/core/Mage/Core/Controller/Varien/Action.php:

abstract class Mage_Core_Controller_Varien_Action
{
    // [...]
    public function preDispatch()
    {
        // [...]
        if ($this->_rewrite()) {
            return; // [What is the purpose if this?]
        }
        // [...]

        // [This is where my event needs to be firing, but this code never gets 
        // executed because the controller is rewritten]
        Mage::dispatchEvent(
            'controller_action_predispatch_'.$this->getFullActionName(),
            array('controller_action'=>$this)
        );

    }
    // [...]
}

I don't know where to start fixing this problem. Anyone out there ever dealt with this before?