jQuery UI - Slider

Hi!
Having some problem with the slider in jQuery. For example I set the startValue to 4000000 but the ui.value, the slider value, returns 3974522 instead. Why? Here´s what I do…


$("#slider_bar1").slider({
    handle: "#slider_handle1",
    minValue: 0,
    maxValue: 4000000*1.5,
    startValue: 4000000,
    start: function(e, ui) {
    },
    stop: function(e, ui) {
        $("#slider_result1").html( Math.round(ui.value) + " :-" );
    },
    slide: function(e, ui) {
        $("#slider_result1").html( Math.round(ui.value) + " :-" );
    }
});