according to the codex, get_header accepts as an argument the name of a php file so that you can use different headers for different page templates eg get_header('home').
using a child theme for thematic, im attempting to do just that with the following template page:
Template Name: special-template
// calling the header.php
special-header is a php file in the same directory as this template, yet the get_header() seems to be ignoring it's argument. Is there something about using thematic as a parent theme that would make this happen?