border-radius on images

[Eik]

I've been using the CSS border-radius property in my stylesheets for some
time now because it's not harmful if the browser doesn't support it and
it's something I've been expecting browsers to implement eventually, so I
was keen to see how Opera would finally handle it in 10.5.

I've noticed that it has no effect on images. If you apply a border to an
image, along with the border-radius properly, you can see the border curve
around and disappear behind the (still square) image.

This is exactly what Mozilla does. Reasonably recent versions of Webkit
round image corners whilst older versions behaved the way Mozilla
currently does (and now Opera too).

I was expecting Opera's implementation to be the same as Apple's rather
than Mozilla, so is this a deliberate decision? I had a look, but can't
find anything in the W3C drafts to say that an image shouldn't have
rounded corners when you use this property, only tables under certain
circumstances.

I've tried adding overflow:hidden and/or display:block but that doesn't
help either.

So, is this an oversight by Opera or the way it should be? *Background*
images are cropped correctly, it's only inline images which aren't.