Quickform required & freeze vs image

It seems that neither freeze nor the required rule work on image input tags. Am I doing something wrong or is there a reason it is so? I am also curious about the date type. There is no obvious (at least to me) way to filter this. I admit I haven't checked the code here, and it might be that this is done automatically, but if somebody could clarify, I'd be grateful. -- --Fredrik When I was a boy I was told that anybody could become President. Now I'm beginning to believe it. -- Clarence Darrow