Setting to prevent users refreshing page with F5 button?

[root@ve1023:Active] config  b virtual bar list
virtual bar {
   snat automap
   pool foo
   destination 172.28.65.152:http
   ip protocol tcp
   rules myrule
   profiles {
      http {}
      stream {}
      tcp {}
   }
}
[root@ve1023:Active] config  b pool foo list
pool foo {
   members 200.200.200.101:http {}
}
[root@ve1023:Active] config  b rule myrule list
rule myrule {
   when HTTP_REQUEST {
        STREAM::disable

        if {[HTTP::version] eq "1.1"} {
                if { [HTTP::header is_keepalive] } {
                        HTTP::header replace "Connection" "Keep-Alive"
                }
        }
}

when HTTP_RESPONSE {
        if {[HTTP::header Content-Type] starts_with "text/"} {
                STREAM::expression "@@@"
                STREAM::enable
        }
}

when STREAM_MATCHED {
        STREAM::disable
}
}

[root@ve1023:Active] config  curl -i http://200.200.200.101
HTTP/1.1 200 OK
Date: Fri, 11 Nov 2011 14:57:59 GMT
Server: Apache/2.2.3 (CentOS)
Last-Modified: Fri, 11 Nov 2011 14:48:14 GMT
ETag: "4183e4-3e-9c564780"
Accept-Ranges: bytes
Content-Length: 62
Connection: close
Content-Type: text/html; charset=UTF-8




This is 101 host.



[root@ve1023:Active] config  curl -i http://172.28.65.152
HTTP/1.1 200 OK
Date: Fri, 11 Nov 2011 14:58:06 GMT
Server: Apache/2.2.3 (CentOS)
Last-Modified: Fri, 11 Nov 2011 14:48:14 GMT
ETag: "4183e4-3e-9c564780"
Accept-Ranges: bytes
Connection: close
Content-Type: text/html; charset=UTF-8
Transfer-Encoding: chunked




This is 101 host.