I know all about adding a region on page.tpl.php and even node.tpl.php in Drupal 6. But, I have a special case where I need to add a region within another region.
In my Drupal install I found the region.tpl.php file which looks like the following:
<div class="<?php print $classes; ?>">
<?php print $content; ?>
</div><!-- /.region -->
I amended it to output my custom region:
<div class="testing <?php print $classes; ?>">
<?php print $content; ?>
<?php if ($inner_sidebar_right): ?>
inside inner-sidebar-right
<div class="inner-sidebar-right"><?php print $inner_sidebar_right; ?></div>
<?php endif; ?>
It doesn't work.
ps: When adding regions in node.tpl.php you have to manipulate _preprocess_node in template.php. Is there perhaps a _preprocess_region function to help accomplish this?