Maximize "down" button missing

Looks like maximize "down" button is missing

"NetworkError: 404 Not Found - http://www-demos.smartclient.com/isomorphic/skins/Enterprise/images/headerIcons/maximize_Down.png"

Here is the example

http://www-demos.smartclient.com/iso...vePortalColumn

Click maximize on any portlet with firebug on

Same result in downloaded 10.0d version