How to force a Webform to be an admin page (Drupal 6)

I’ve created a WebForm and I’ve been modifying it with hook_form_alter inside a custom module. Another thing I wanted to do is make the page be an admin page, I did changed the path to ‘admin/mypath’ but it didn’t worked.The solution I’ve come with is divided in two parts:

1- Show the admin theme

function mymodule_init(){
$path = drupal_get_path_alias($_GET['q']);
 if($path == 'admin/mypath'){
 global $custom_theme;
 $custom_theme = variable_get('admin_theme', '0');
 drupal_add_css(drupal_get_path('module', 'system') .'/admin.css', 'module');

2- Restrict the access

function mymodule_nodeapi (&$node, $op){ 
// Load the currently logged in user. 
global $user; 
if($node->path == 'admin/mypath' && $op == 'view'){
 // Check if the user has the 'ATD Staff' role.
 else if (in_array('my_allowed_role', $user->roles)) {

No need to say, if somebody has a better solution please write a comment here.