А слабо было использовать разные css файлы и подключать их через Conditional comments:
Код:
<!--[if IE]>
According to the conditional comment this is Internet Explorer
<![endif]-->
<!--[if IE 5]>
According to the conditional comment this is Internet Explorer 5
<![endif]-->
<!--[if IE 5.0]>
According to the conditional comment this is Internet Explorer 5.0
<![endif]-->
<!--[if IE 5.5]>
According to the conditional comment this is Internet Explorer 5.5
<![endif]-->
<!--[if IE 6]>
According to the conditional comment this is Internet Explorer 6
<![endif]-->
<!--[if gte IE 5]>
According to the conditional comment this is Internet Explorer 5 and up
<![endif]-->
<!--[if lt IE 6]>
According to the conditional comment this is Internet Explorer lower than 6
<![endif]-->
<!--[if lte IE 5.5]>
According to the conditional comment this is Internet Explorer lower or equal to 5.5
<![endif]-->
в вашем xhtml файле?