function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; 
  document.MM_sr=new Array;
  for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){
	   document.MM_sr[j++]=x;
	   if(!x.oSrc) x.oSrc=x.src;
	   x.src=a[i+2];
	}
}

function validateEmail(email) {
   var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
   return reg.test(email);
}
function checkForm(form){
	var valid = true;
	var message = "";
	if(form.name.value.length < 2){
		message += "Please enter a name.\n";
		valid = false;
	}
	if(!validateEmail(form.email.value)){
		message += "Please enter a valid e-mail address.\n";
		valid = false;
	}
	if(!valid){
		alert(message);
	}
	return valid;
}

function checkEmail(email) {

	if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(email)) {

		return true;

	}else {

		return false;

	}

}
function maxCategorySelect(maxnum){
	var categorynum = document.update_categories['category[]'].length;
	var categories = document.update_categories['category[]'];
	var checkednum = 0;
	for(i=0; i<categorynum; i++){
		var checkbox = categories[i];
		if(checkbox.checked){
			checkednum++;
			if(checkednum > maxnum){
				alert('You may select a maximum of ' + maxnum + ' categories');
				return false;
			}
		}
	}
}