function validate_email(field, invalidmessage)
{
	with (field)
	{
		apos=value.indexOf("@");
		dotpos=value.lastIndexOf(".");
		if (apos < 1 || dotpos - apos < 2) {
		    hide_all_validaton_messages();
		    document.getElementById(invalidmessage).style.visibility = 'visible';
			return false;
		}else{
			return true;
		}
	}
}

function validate_required(field, invalidmessage)
{
	with (field)
	{
		if (value==null||value==""){
		    hide_all_validaton_messages();
		    var element = document.getElementById(invalidmessage).style.visibility = 'visible';
			return false;
		}else{
			return true;
		}
	}
}

function hide_all_validaton_messages() 
{
    document.getElementById("namemessage").style.visibility = 'hidden';
    document.getElementById("emailmessage").style.visibility = 'hidden';
    document.getElementById("messagemessage").style.visibility = 'hidden';
}


function validate_form(thisform)
{
	with (thisform)
	{
	    if (validate_required(name, "namemessage") == false) {
		    name.focus(); return false;
        } else if (validate_required(message, "messagemessage") == false) {
		    message.focus(); return false;
		} else if (validate_email(email, "emailmessage") == false) {
			email.focus();return false;
		}else{
			return true;
		}
	}
}