Currently, the Input Format field is implemented as:

<?php
$form
['site_map_message_format'] = filter_form(variable_get('site_map_message_format', FILTER_FORMAT_DEFAULT));
?>

However this stores the form element under the default name, "format". When system_settings_form handles the submission it stores the selection in a variable called format, not site_map_message_format.

The solution is to implement filter_format with the parents array site to the form element name... Like this:

<?php
$form
['site_map_message_format'] = filter_form(variable_get('site_map_message_format', FILTER_FORMAT_DEFAULT), NULL, array('site_map_message_format'));
?>

I can confirm this fix works for the site I'm working on.

Files: 
CommentFileSizeAuthor
#1 site_map.input-format-fix.patch891 bytesnicholasThompson

Comments

StatusFileSize
new891 bytes

Patch Attached...

This is still an issue with 6.x-2.1 which I am using.
Could this be addressed, please?

I just needed the Full HTML option to be used so I inserted into drupal_variable manually as a workaround:

name: site_map_message_format
value: i:2;

Status:Needs review» Fixed

Thanks for reminding me of this!

Committed to 6--2-dev.

Status:Fixed» Closed (fixed)

Automatically closed -- issue fixed for 2 weeks with no activity.