Collapsible containers with Advanced Forum

I am trying to make this forum hack work on advanced forums, the collapsible containers. http://drupal.org/node/202542

However, I am running into a bit of a problem with step 3.

Using a text editor, create a file and give it the name "forum_list.tpl.php" using the following code. Put it in your active theme folder.

and step 4

In a text editor, create a new file called "template.php" and copy the following snippet into the file. If a "template.php" file already exists, simply add the snippet remembering to omit the opening and closing PHP tags

/**
* This snippet tells Drupal to override the forum_list function
* and load a custom forum_list.tpl.php layout file
* in the theme folder
*/
function phptemplate_forum_list($forums, $parents, $tid) {
return _phptemplate_callback('forum_list', array('forums' => $forums, 'parents' =>$parents, 'tid' =>$tid));
}

I am then getting this error after those steps
Fatal error: Cannot redeclare phptemplate_forum_list() (previously declared in /home/timescom/public_html/carz4/modules/advanced_forum/advanced_forum.module:370) in /home/timescom/public_html/carz4/themes/garland/template.php on line 13

I know it's something simple, but I don't know what to exactly do!