Hiding this decl from NS?

I suppose this is a bit off topic, but I'm told that XHTML+SMIL requires the following in the HEAD section:

<?IMPORT namespace="t" implementation="#default#time2">

The problem is that Netscape 4.7 displays this raw text at the top of the page, even though it's in the HEAD. Is there a way of hiding it from Netscape, or is it strictly necessary for XHTML+SMIL?