Permalinks in 3.0

Hi,

I am a new WordPress user. I installed version 3.0 on Ubuntu 10.4. I wanted to change my permalinks. The links on the generated html documents look correct and when I edit a document, the permalink also is proposed correctly. However, when clicking on a link, I get a 404 – not found message, issued by apache2.

I read about issues with previous content. Hence, I created a new entry. Unfortunately, I get the same behavior.

Then, I changed back to the default permalink (http://site.com?p=123). As a result, all entries, independent under which permalink-setting they were created, are working as expected.

Is this a bug in 3.0?