maybie sepultura, you could explain in more detail the situation you need to hide your meta tags? I am finding it hard to find a reason why imitating meta tags would be a security issue (or do you mean manipulating meta tags?)

For instance, Cnn hides its Meta Tags, is it ILLEGAL?
go to www.cnn.com and you will find
<html lang="en">
<head>
<title>CNN.com International</title>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1">
<meta http-equiv="refresh" content="1800">
<title>CNN.com</title><link rel="Start" href="/">

How is that hiding their meta tags??

sittingduck