Just for the record:
The problem was also covered in this post:
viewtopic.php?f=7&t=177&start=10#p2567
You'll find the solution there

Hi Paul,

that's it - thanks a lot!
Works like a charm now

Have a nice day and thanks again.

Hi Paul, on my wiki (http://geld-verdienen-wiki.de) I also can't click on the first three suggestions (it's the same on paulgu.com by the way!). The other suggestions work properly and you'll get the right article when you click on them. I'm using GuMaxVN and firefox 3.6.13. You know how we can fix ...

Hi Paul, Hi Wikinger, I've got similar issues on my wiki (http://geld-verdienen-wiki.de). If you type some letters the auto suggestion shows the according articles but you can't click on the first, second and third suggestion. However the fourth suggestion works. And yes, it's the same on your searc...