Recent Global Posts Feed - No Feed Results

I recently upgraded our WPMU 2.7 installation to 3.0

I upgraded the global posts feed, and when i go to the posts feed URL it is working. It does not, however, work with the global posts widget or as I try to embed it in my page (which is how it was setup previously to this).

this is how it is being called in the page

$feed_url = get_global_feed_url();

feedList(array("rss_feed_url"=> $feed_url,
"num_items" => 15,
"before" => '<div class="post">',
"after" => '</div>',
"description_separator" => '',
"max_characters" => 200,
"max_char_wordbreak" => true

Any help much appreciated!