function ch(){
	if((document.linkfrm.stitle.value=="")||(document.linkfrm.surl.value=="")||(document.linkfrm.description.value=="")||(document.linkfrm.email.value=="")||(document.linkfrm.rurl.value=="")){
		alert("Please fill in the form!");
		return false;
		}
	if(document.linkfrm.description.value.length>150){
		alert("Your description exceeds 150 chars");
		return false;
	   }
    var mailaddr=document.linkfrm.email.value;
    if((mailaddr.indexOf("@")==-1)||(mailaddr.indexOf(".")==-1)||(mailaddr.indexOf("@")==0)||(mailaddr.indexOf(".")==0)||(mailaddr.lastIndexOf("@")==mailaddr.length-1)||(mailaddr.lastIndexOf(".")==mailaddr.length-1)){
       alert("Please input correct mail address!");
       return false;
      }
}