Changing HTTP Reponse status code

[root@ve10:Active] config  b virtual bar list
virtual bar {
   snat automap
   pool foo
   destination 172.28.19.252:80
   ip protocol 6
   rules myrule
   profiles {
      http {}
      tcp {}
   }
}
[root@ve10:Active] config  b pool foo list
pool foo {
   members 200.200.200.101:80 {}
}
[root@ve10:Active] config  b rule myrule list
rule myrule {
   when HTTP_RESPONSE {
  if { [HTTP::status] == 404 } {
    HTTP::respond 200
  }
}
}

 test

[root@ve10:Active] config  ssldump -Aed -nni 0.0 port 80
New TCP connection 1: 172.18.204.228(49530) <-> 172.28.19.252(80)
1373588986.4110 (0.0048)  C>S
---------------------------------------------------------------
GET /not_real_uri HTTP/1.1
Host: 172.28.19.252
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:22.0) Gecko/20100101 Firefox/22.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive

---------------------------------------------------------------

New TCP connection 2: 200.200.200.10(49530) <-> 200.200.200.101(80)
1373588986.4121 (0.0010)  C>S
---------------------------------------------------------------
GET /not_real_uri HTTP/1.1
Host: 172.28.19.252
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:22.0) Gecko/20100101 Firefox/22.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Connection: keep-alive

---------------------------------------------------------------

1373588986.4132 (0.0010)  S>C
---------------------------------------------------------------
HTTP/1.1 404 Not Found
Date: Fri, 12 Jul 2013 00:40:19 GMT
Server: Apache/2.2.3 (CentOS)
Content-Length: 288
Connection: close
Content-Type: text/html; charset=iso-8859-1

...snipped...
---------------------------------------------------------------

1373588986.4133 (0.0022)  S>C
---------------------------------------------------------------
HTTP/1.0 200 OK
Server: BigIP
Connection: close
Content-Length: 0

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