I am working with PHP 5.2.10 (I downgraded from 5.3) and after I press "Save and continue" on the "vBulletin to Drupal" module's page I get the following errors:

Warning: include_once(./includes/unicode.entities.inc) [function.include-once]: failed to open stream: No such file or directory in /home/carlos/www/beta/drupal-6.22/includes/unicode.inc on line 339

Warning: include_once() [function.include]: Failed opening './includes/unicode.entities.inc' for inclusion (include_path='.:/usr/share/php:/usr/share/pear') in /home/carlos/www/beta/drupal-6.22/includes/unicode.inc on line 339

Warning: include_once(./includes/unicode.entities.inc) [function.include-once]: failed to open stream: No such file or directory in /home/carlos/www/beta/drupal-6.22/includes/unicode.inc on line 339

Warning: include_once() [function.include]: Failed opening './includes/unicode.entities.inc' for inclusion (include_path='.:/usr/share/php:/usr/share/pear') in /home/carlos/www/beta/drupal-6.22/includes/unicode.inc on line 339

Fatal error: Call to undefined function update_get_projects() in /home/carlos/www/beta/drupal-6.22/modules/update/update.module on line 358