HTTP Re-Direct uri replace?

I don't think you'd want to rewrite all 302s to 301s as that tells the client and any intermediate proxies to permanently cache the redirect.

If you want to skip just Locations which contain 2fwusjt568 you could use something like this:

when HTTP_RESPONSE {
    if { [HTTP::status] == 302  and not ([HTTP::header Location] contains "2fwusjt568")} {
      HTTP::respond 301 Location [HTTP::header Location] 
   }
}

Aaron