Actually it can be done cross-browser in an iframe with some javascript, and that allows for custom graphical scrollbars as well.
Looks great, check it out in this template over at Zymic.com:
http://zymic.com/clicks/download.php?title=t2
IMHO catering for IE specific non-standard tags will muck up your designs, and support the evil overlord Bill. Yeah there's a load of nifty fx and stuff that you can do in IE, but they've been developed by MinisculeSoft because they thought they knew what was best.
Me no like.
Mozilla good lizard.
IE bad juju.
