CSS tweak for drop down menu

I have implemented a jQuery drop down menu and had to make some adjustments to the styles so that a particular embedded font is used for the main nav and then a particular background colour and font is used for the drop down menus. The menu and files that will be supplied are working and look exactly how they should in IE 8, Safari 5, and FireFox 3.5 but it doesn't displaying correctly in IE 6 and possibly other browsers. I require someone with good CSS / HTML skills who can modify the CSS in order for it to display properly in all browsers including IE 6, and Chrome.