It should replace all of the characters he listed. Char's #0-31 are all control characters which can't be used in filenames.
Of course, although they're not expressly forbidden in any IRC RFC, it's pretty stupid to allow them in a channel name since they're all non-printable and so may appear as spaces or not appear at all in many fonts. Not to mention the problems arising from a channel name having characters which most IRC clients interpret as text-formatting.
