function validEmail(email) {
	invalidChars = " /:,;"
	if ((email=="") || (email==null)) {
		return false;
	}
	for (i=0; i<invalidChars.length; i++) {
		badChar = invalidChars.charAt(i)
		if (email.indexOf(badChar,0) > -1) {
			return false;
		}
	}
	atPos = email.indexOf("@",1)
	if (atPos == -1) {
		return false;
	}
	if (email.indexOf("@",atPos+1) > -1) {
		return false;
	}
	periodPos = email.indexOf(".",atPos)
	if (periodPos == -1) {
		return false;
	}
	if (periodPos+3 > email.length) {
		return false;
	}
	return true;
}