Preferably it would be setup with:
/layouts/default.php
/layouts/oneColumn.php

Then in the controllers you can do $this->_helper->layout->setLayout('default'); or $this->_helper->layout->setLayout('oneColumn');

__________________
Zend Framework Resources: Zend Webinars | Reference Manual | API Docs | Books | FreeNode: #zftalk
Getting Started Tutorials: Getting started with ZF | Getting started with Zend Auth