Sidebar mod

I'm using the super river_activity_3C and have added this mod to the start.php which inserts an advert at the top of the sidebar...

elgg_extend_view('page/elements/sidebar', 'page/elements/smart_phone','700');

 

I have also applied this mod to all other sidebars

views/default/page/elements/sidebar.php via my theme plugin...

 

$river_body = '<iframe src="http://www.mysite.com/community/ads/iphone/index.htm" width="240" height="444" scrolling="no" frameborder="0" owerflow="hidden" ></iframe>';

echo elgg_view_module($box_view, $title, $river_body);

 

 

Both work great but my problem is that both ads are displayed on the river_activity_3C page. How can I prevent the site-wide mod displaying on that activity page?