String request, data, reply;


http.ClearHeaders();
request << "Content-Length: "<< (int) data.GetLength()<<"\r\n";
request << "Content-Type: txt/xml\r\n\r\n";
http.Post();
http.std_headers = true;
http.AddHeaders(request);

data << "var1=hello&var2=fallingdutch";

http.AddHeaders(data);
reply = http.Execute();