Change HTTP request string

i understand stream profile changes both request and response payload. profile affects payload stream profile can modify. for example, when not using http profile, stream profile can change content in http request header (tcp payload).

e.g.

[root@ve10:Active] config  b virtual bar list
virtual bar {
   snat automap
   pool foo
   destination 172.28.19.79:80
   ip protocol 6
   profiles {
      mystream {}
      tcp {}
   }
}
[root@ve10:Active] config  b pool foo list
pool foo {
   members 200.200.200.101:80 {}
}
[root@ve10:Active] config  b profile mystream list
profile stream mystream {
   defaults from stream
   source "something"
   target "somethingelse"
}

[root@ve10:Active] config  ssldump -Aed -nni 0.0 port 80
New TCP connection 1: 172.28.19.251(44024) <-> 172.28.19.79(80)
1350399358.6589 (0.0010)  C>S
---------------------------------------------------------------
HEAD /something/test HTTP/1.1
User-Agent: curl/7.15.5 (i686-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
Host: 172.28.19.79
Accept: */*

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

New TCP connection 2: 200.200.200.10(44024) <-> 200.200.200.101(80)
1350399358.6599 (0.0010)  C>S
---------------------------------------------------------------
HEAD /somethingelse/test HTTP/1.1
User-Agent: curl/7.15.5 (i686-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
Host: 172.28.19.79
Accept: */*

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