user_create_user and user_update_user functions do not validate auth, lang or theme

Test 1 - Creating a user. Create a user on your site. Visit <yoursite>/admin/tool/langimport/index.php and install a new language pack. Place the attached 'test_create_user.php' file into your Moodle directory. Use the attached script to create a user with the 'auth' setting to something that does not exist, eg. "blahblah". An error should be returned stating this is not valid. Use the attached script to create a user with the 'auth' setting to 'mnet'. An error should be returned stating why this can not be changed. Try again with a valid auth method (but different than the one they are currently using) and check that the user's 'auth' setting is correct in the DB (note the script will print the user's data from the DB if there are no exceptions). Use the function to create a user with the 'lang' setting to something that does not exist. An error should be returned stating this is not valid. Try again using a valid language and check that it worked. Use the function to create a user with the 'theme' setting to something that does not exist. An error should be returned stating this is not valid. Try again with a valid theme and check that it worked. Test 2 - Updating a user Create a user on your site. Visit <yoursite>/admin/tool/langimport/index.php and install a new language pack. Place the attached 'test_update_user.php' file into your Moodle directory. Use the attached script to update the 'auth' setting to something that does not exist, eg. "blahblah". An error should be returned stating this is not valid. Use the attached script to update the 'auth' setting to 'mnet'. An error should be returned stating why this can not be changed. Try again with a valid auth method (but different than the one they are currently using) and check that the user's 'auth' setting has been changed in the DB (note the script will print the user's data from the DB if there are no exceptions). Use the function to update the 'lang' setting for this user to something that does not exist. An error should be returned stating this is not valid. Try again using a valid language (but different than the one they are currently using) and check that it worked. Use the function to update the 'theme' setting to something that does not exist. An error should be returned stating this is not valid. Try again with a valid theme (but different than the one they are currently using) and check that the user's 'theme' setting has been changed. Now remove the change to the $user variable in the script. Check that it works and none of the values changed.