Dashoard: "visual editing" lacking

Hi,usually, when in the dashboard i.o. to write a post or page, the editing area is usually wysiwyg and you have the choice between visual and html editing.

But in in one of my wordpress sites, that area is only in html mode, with no possibility to change to visual mode.

I can′t find a possibility to get to the usual look. Is there any chance to get back to the usual look?

btw, the visual edit even lacked before upgrading to 3.2.1 (I was hoping the upgrade would fix that, but it still looks that odd way)

Any idea? Thanx in advance