hook_theme() specifying arguments incorrectly

The implementation of hook_theme() isn't specifying the arguments correctly. It should be array('name_of_variable' => 'default value'). Right now it's specified more like this array(0 => 'name_of_variable'), which means in the (very unlikely) situation that a user made a lt-username-title.tpl.php file, the variable name would be called $0 instead of $name_of_variable.

This has already been corrected in the Drupal 7 version.