For those of you that are totally stuck and have looked at every tutorial, specifically the one found here: http://prattski.com/2010/06/24/magento-overriding-core-files-blocks-models-resources-controllers/, on Overriding Controllers, and you still can’t seem to get it to work, this solution may work for you:
In your /app/etc/modules/Company_Module.xml file, ensure <codePool> is spelled this way. <codepool> will NOT WORK and Magento will silently fall back to the core controller.
Here is the full file for your reference:
<?xml version=”1.0″?>
<config>
<modules>
<Company_Module>
<active>true</active>
<codePool>local</codePool>
</Company_Module>
</modules>
</config>
