[Mediawiki-l] Trying to protect/unprotect pages with custom group

[Rowe, Dolores A]

Teammates,

In a version 1.15.3 wiki, I am trying to set up a custom group that can protect/unprotect pages.
I use the following statements in the LocalSettings.php file.

$wgGroupPermissions['Build_group']['edit'] = true;
$wgGroupPermissions['Build_group']['editprotected'] = true;
$wgGroupPermissions['Build_group']['protect'] = true;

However, when I go to an unprotected page, and select the protect tab at the top of the page,
I do not have the option to allow only the Build_group to edit or move the page.

I only have 3 options:
"Allow all users"
"Block new and unregistered users"
"Administrators only"
Is there another setting that I need to add to my permissions ?
thanks,
Lori