may not be the best way, but i know it works since i use it at the moment (too busy trying to get other things corrected)...
in the customer/home.tpl file i have:
Code:
<link rel="stylesheet" href="{$SkinDir}/{#CSSFile#}">
<!--[if lt IE 7]>
<link rel="stylesheet" href="{$SkinDir}/style_ie.css">
<![endif]-->
i use 2 style sheets, one for the old IE browsers and the other for everything else
(i believe that you would have to put it in the order that i have above)