function isValidEmail(emailfobj) {
	var emailPattern = /^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
	var isvalid = emailPattern.test(emailfobj.value);
	if (!isvalid) {
		emailfobj.value = '';
		emailfobj.focus();
	}
	return isvalid;
}

function comparePasswords(passfobj1,passfobj2) {
	var isvalid = ((passfobj1.value == passfobj2.value) && (passfobj1.value.length));
	if (!isvalid) {
		passfobj1.value = '';
		passfobj2.value = '';
		passfobj1.focus();
	}
	return isvalid;
}

function checkLength(fobj) {
	var isvalid = (fobj.value.length > 0);
	if (!isvalid) fobj.focus();
	return isvalid;
}

function radioHasBeenClicked(radiofobj) {
	var has_been_clicked = false;
	for (i = 0; i < radiofobj.length; i++) {
		if (radiofobj[i].checked) has_been_clicked = true;
	}
	return has_been_clicked;
}


function checkboxWasChecked(fobj) {
	var was_checked = false;
	if (fobj.checked == 1) was_checked = true;
	if (!was_checked) {
		fobj.focus();
	}
	return was_checked;
}

function checkExistenceOfEmail(eobj) {
	ok2go = false;
	for ( var i = md5emails.length-1; i>=0; --i ){
		if ( md5emails[i] == hex_md5(eobj.value) ) {
		ok2go = true;
		}
	}
	if (!ok2go) alert('Sorry, that email address was not found in our database.');
	return ok2go;
}