why didn't you include the dll?

not necessarily, works withoutdll.
script is targeted at English-speaking audience, as you, so I did not consider it necessary to do so. more simply: forgot =)

If you really want, you can download here: http://xise.nl/mirc/idna.zip

Example, I from Russia and we have our domain ".рф"
http://президент.рф -> IDNA (idna.dll,encode) -> http://xn--d1abbgf6aiiy.xn--p1ai