$(function(){
 // $Date is perl of course 
var json=jQuery.parseJSON(\'{"DATE":"'.$Date.'"}\');

  json["address"]="123 some street";
  // other functions generate more fields. and call postM()
  postM();

function postM(){
 $.ajax({
    url: "params.pl",
    type: "GET",
    processData: false,
    data: JSON.stringify(json),
    dataType: "text",
    async: true,
    success: function(msg){ alert("perl says: "+msg); }
 }); // ajax
} // postM

}); // jquery