Switching tabs results in empty tabs

Hi,

I have a weird problem in my EasyDiscuss setup.

I have only two categories created yet, and posted one topic in one of those categories.

When I visit this topic, there are a few tabs above the topic, All, Popular and Latest.
When first navigating to this page, I also see my one topic.

When I click one of those tabs, however, f.i. Latest, I get nothing, and when I switch back to tab All, also get nothing.
So my topic disappears.... and won't come back until I navigate through my menu to this page again.

Ay thoughts on this?

Corine