static function OnBeforeRequest(oSession: Session) 
{ 
if(oSession.uriContains("http://www.text.com/next?cyt=1"))
{
var strBody=oSession.GetRequestBodyAsString();                                                    
  strBody=strBody.replace("step=ashf87afs0a2e4","step=qarker11s77ar");
  strBody=strBody.replace("step=qarker11s77ar","step=qarker22s88ar");
     oSession.utilSetRequestBody(strBody);
}
}