What bit do you exactly mean? I don't see any error on that page...
if you mean:
[noparse][b]bold text! :)[/b][/noparse] = [b]bold text! :)[/b]
Then that's exactly what [noparse] will do, as it means
"do not parse any enclosed tags". It is absolutely correct.
eg, if you write:
[noparse][b]hello [i]world[/i][/b][/noparse]
then the output will be:
[b]hello [i]world[/i][/b]
and not:
hello world
because everything enclosed in the [noparse] tags will be interpreted as
literal text, not as special tags or whatever.
EDIT: WTF at all these replies... lol