You need to
before you can comment on or make changes to this bug.
The Mozilla bug (referenced in the URL) was originally filed by David Hyatt and this is now fixed and will be included in the next version of Firefox.
Implementing -webkit-image-rect would allow CSS spriting without introducing dummy DOM nodes.
See also http://www.w3.org/TR/css3-images / http://dev.w3.org/csswg/css3-images/