Andrus

hey i need something to restrict alot of funny chars in the username right now i got this // check the username for bad chars if(!eregi("[A-Z]",$username)){ echo '<script language="Javascript">alert ("Bad characters in username")</script>'; include("index.html"); exit(); } but it still allows weird looking characters like Ũ and stuff, how do i restrict it to only A-Z and a-z