function forwardFriends(){
	if(!isValidEmail(document.form_forward.submit_mail.value) || document.form_forward.submit_mail.value == ""){
		alert("Invalid email!");
	}else{
		l = escape(window.location);
		MM_openBrWindow('http://www.sinchungkai.org.hk/demo/script/forward.php?url='+l+"&submit_mail="+document.form_forward.submit_mail.value, 'forward', 'width = 200 height = 100');
		document.form_forward.submit_mail.value = "";
	}	
}
function isValidEmail(emailAddr) {
  if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(emailAddr));
    return (true)
}
function checkSubscribe(){
	if(!isValidEmail(document.form1.submit_mail.value) || document.form1.submit_mail.value == ""){
		alert("Invalid email!");
	}else{
		url = "http://www.sinchungkai.org.hk/demo/script/mailer.php?submit_mail="+document.form1.submit_mail.value;
		MM_openBrWindow(url,"mailer","width = 200 height = 100");
		document.form1.submit_mail.value = "";
	}	
}
function searchSubmit(){
	if(document.searchForm.query.value != ""){
		document.searchForm.submit();
	}else{
		alert("please enter your search keyword!");
	}
}