IE 8 - button's not working

Hello,

I've been implementing the ckeditor, but I'm unable to use it in IE 8. The button's (source, bold, italic, every single one) don't work (I can click them, but nothing happens). I am not sure if the events are triggered because I don't know which function they call. I could reproducre the problem when trying out the samples provided by ckeditor, so it has nothing to do with my personal ckeditor configuration.

The contextmenu (right-click menu) DOES work, so only the buttons in the menu aren't working.

I am using ckeditor 4.2, internet explorer 8, I reduced the security level to minimum, added the site to the trusted/intranet zone (with minimal security), etc. but nothing helps.

If I try the samples with IE 10 (other pc) in compatibilitymode IE 8, the ckeditor works.

Since ckeditor is supporting IE 8, what could be the cause of this? If you could point me in a direction I could trace the problem, but at the moment I don't have a clue what could be wrong.

Thanks in advance.