Set Body class and / or ID?

Is there a way to set a body class or ID to a CKEditor instance?

In FCKEditor, there obviously used to be a "bodyClass" / "bodyId" config setting but it doesn't seem to work in CKEditor.

I have played around with CKEditor.document.getBody() but have so far only managed to get the surrounding document's body element, not the editor body.

Help would be greatly appreciated.