URI Rewrite

Is it for that exact string? or do you want to add an "X" to a certain part of the URI.

I would accomplish your example via the following. I'm assuming you want to redirect if 1) the host is "www.xyz.com" and 2) the URI is "/something/howto.html"

when HTTP_REQUEST {
if { [string tolower [HTTP::host]] eq "www.xyz.com" and [string tolower [HTTP::uri]] eq "/something/howto.html" } {
HTTP::redirect "http://www.xyz.com/somethingX/howto.html" } }