clipped from: walkthrough.ifupdown.com   

Don't let people fool you when they say to put the following into your XHTML.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html 
     PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

Don't fall for it. If you put that xml definition before the Document Type, IE6 and probably IE7 will forget your standard compliance you really want.

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