function validEmailChars(parField) {
// convert the string to lower case
// then check each char to see if it is in the list of valid chars
// if the char is deemed to be invalid, stop and return false
// go on to the next char
// if you're still hanging in there at the end, the string must be valid, so return true

validchars = "abcdefghijklmnopqrstuvwxyz0123456789&._-@"
str = parField.toLowerCase();
for (var i = 0; i < str.length; i++) 
	{
	chr = str.substring(i, i + 1);
	if (validchars.indexOf(chr) == "-1")
		{
        return false;
		}
	}
return true;	
}