function nmbCheck(elem, val){
        if (!parseInt(elem.value)){
            elem.value= val ? val : '';
        }
    }

    function kpCheck(e){
        var unicode=e.charCode? e.charCode : e.keyCode
        if (unicode!=8 && unicode!=9 && unicode!=35 && unicode!=36 && unicode!=46){ //if the key isn't the backspace, Home, End, Delete key (which we should allow)
            if (unicode<48||unicode>57) //if not a number
            return false //disable key press
        } else {
            nmbCheck(this);
        }
    }

    function init(){
        frm = document.forms['searchForm'];

        elem1 = frm.elements["d"];
        elem1.onfocus = function () {nmbCheck(elem1)}
        elem1.onblur = function () {nmbCheck(elem1, 'dd')}
        nmbCheck(elem1, 'dd');

        elem2 = frm.elements["m"];
        elem2.onfocus = function () {nmbCheck(elem2)}
        elem2.onblur = function () {nmbCheck(elem2, 'mm')}
        nmbCheck(elem2, 'mm');

        elem3 = frm.elements["y"];
        elem3.onfocus = function () {nmbCheck(elem3)}
        elem3.onblur = function () {nmbCheck(elem3, 'yyyy')}
        nmbCheck(elem3, 'yyyy');
    }

    function callBack(result, form){
        if (result){
            msg = "Ihre Anfrage wurde an uns weitergeleitet. Vielen Dank!";
            alert(msg);
    
            frm = document.forms[form];
            if (frm)    frm.reset();
        } else {
            msg = "Error sending information!";
            alert(msg);
        }
    }