Problem with javascript in Blackberry (OS 4.6) native browser

When call to this ajax function is repeated a second time, response is appended (not replaced), to info id. This occu开发者_Python百科rs both when I use innerHTML and XUI shortcut function. Code works properly on IE and Mozilla desktop.

 function ajax_call()
 {
    var full_date = document.getElementById('from_date').value;             
    x$('#status').xhr('myPgm.pgm?userid=/%userid%/&calDate=' +full_date,
    function(){                 
        //document.getElementById('info').innerHTML = this.responseText;
        x$('#info').html(this.responseText);                
     }
   ); 
}

What does ajax call return? Is that doubled up?