[cut]
Craig's information is correct, but the "ugly tricks" comment isn't fair. Those "ugly tricks" aren't that bad, and they've been WELL documented since 1998 in RFC 2317!
Those, well documented ,in rfc, tricks are, indeed, UGLY tricks. Having something well documented does not make it beautiful.
Honestly, there are too much classful/octal ugly shit still floating around. [cut]