Xccessors is a script I made which implements the legacy methods for defining and looking up object accessors (getters and setters) of objects in JavaScript using ECMAScript 3.1’s accessors standard. This is aimed at adding support for the legacy method in IE8 RC1. Read more on the Xccessors project page. There is also a demo you can try out.

Update: I just tested the script in IE8 RC1 and it seems that IE8 RC1 only supports getters and setters on the DOM and the window object. So as long as you are setting an accessor on the window object or a DOM element, Xccessors should work fine.