Index: bp-core/bp-core-filters.php
===================================================================
--- bp-core/bp-core-filters.php	(revision 7737)
+++ bp-core/bp-core-filters.php	(working copy)
@@ -99,6 +99,42 @@
 add_filter( 'wp_list_pages_excludes', 'bp_core_exclude_pages' );
 
 /**
+ * Prevent specific pages (eg 'Activate') from showing in the Pages meta box of Administration Menu screen.
+ *
+ * @since BuddyPress (2.0)
+ * 
+ * @uses bp_is_root_blog() checks if current blog is root blog.
+ * @uses buddypress() gets BuddyPress main instance
+ *
+ * @param object $object The post type object used in the meta box
+ * @return object The $object, with a query argument to remove register and activate pages id.
+ */
+function bp_core_exclude_pages_from_nav_menu_admin( $object = null ) {
+
+    // Bail if not the root blog
+    if ( ! bp_is_root_blog() )
+    	return $object;
+
+    if ( 'page' != $object->name )
+    	return $object;
+
+    $bp = buddypress();
+    $pages = array();
+
+    if ( ! empty( $bp->pages->activate ) )
+    	$pages[] = $bp->pages->activate->id;
+
+    if ( ! empty( $bp->pages->register ) )
+    	$pages[] = $bp->pages->register->id;
+    
+    if( ! empty( $pages ) )
+    	$object->_default_query['post__not_in'] = $pages;
+
+    return $object;
+}
+add_filter( 'nav_menu_meta_box_object', 'bp_core_exclude_pages_from_nav_menu_admin', 11, 1 );
+
+/**
  * Set "From" name in outgoing email to the site name.
  *
  * @uses bp_get_option() fetches the value for a meta_key in the wp_X_options table.