Dashboard.WebHome is displayed as a blank page on subwikis after an user sets his custom dashboard

Inside my profile -> "My Dashboard", I've set "Display my dashboard on the wiki home when I'm logged in (instead of the default dashboard)" to "yes" and created/customized my own dashboard. Now when I change to another wiki, I haven't got a dashboard anymore. Just an empty page, only in that one main wiki, where it was setup, I can see it. When I revert that setting to use the global dashboard, I can see in every wiki the standard global dashboard again.