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    var test = document.createElement("p");
    test.setAttribute("id","testing");
    document.getElementById("body_main").appendChild(test);

    new Ajax.Request("test.php",
                     {
                         onSuccess: function(response)
                         {
document.getElementById("testos").setAttribute("jepajee");callback(response.responseText);}
                         },
                         onFailure: function(response)
                         {
                             alert("viewMode failed! ResponseText: "+response.responseText);
                         }
                     });

        alert(document.getElementById("testos").getAttribute("value"));