I’ve been playing around with Drupal for work and wanted to use mod_auth_kerb to authenticate Drupal users. The Webserver Auth module seemed helpful, but only worked in Drupal 4. I got the module working with Drupal 5.5 running on Apache 2.2.3 using mod_auth_kerb 5.1.
Link to my patch to make webserver_auth-4.7.x-1.x-dev work with Drupal 5.x
Link to documentation on updating Drupal 4.7 modules to Drupal 5.