function maybe_send_form(form){
	if(!form) form=document.forms[0];
	var elements=form.elements;
	for(var i=0; i<elements.length; i++){
		var element=elements[i];
		var required=element.getAttribute("required");
		if(required){
			var title=element.getAttribute("title");
			var name=element.getAttribute("name");
			var value=element.value;
			var title_or_name=title?title:name;
			if(!value){
				alert("Пожалуйста, заполните поле \""+title_or_name+"\"");
				return;
			}
		}
	}
	form.submit();
}

function getBrowserInfo() {
    var t,v = undefined;
   
    if (window.chrome) t = 'Chrome';
    else if (window.opera) t = 'Opera';
    else if (document.all) {
        t = 'IE';
        var nv = navigator.appVersion;
        var s = nv.indexOf('MSIE')+5;
        v = nv.substring(s,s+1);
    }
    else if (navigator.appName) t = 'Netscape';
   
    return {type:t,version:v};
}

function bookmark(a){
    var url = window.document.location;
    var title = window.document.title;
    var b = getBrowserInfo();
   
    if (b.type == 'IE' && 8 >= b.version && b.version >= 4) window.external.AddFavorite(url,title);
    else if (b.type == 'Opera') {
        a.href = url;
        a.rel = "sidebar";
        a.title = url+','+title;
        return true;
    }
    else if (b.type == "Netscape") window.sidebar.addPanel(title,url,"");
    else alert("Нажмите CTRL-D, чтобы добавить страницу в закладки.");
    return false;
}