Dê uma olhada no idn
:
[U] net-dns/libidn
Available versions: 1.22 (~)1.22-r1 {doc elibc_FreeBSD emacs java mono nls static-libs}
Installed versions: 1.22(03:12:19 PM 07/04/2011)(nls static-libs -doc -elibc_FreeBSD -emacs -java -mono)
Homepage: http://www.gnu.org/software/libidn/
Description: Internationalized Domain Names (IDN) implementation
Por exemplo:
$ echo "президент.рф" | idn
xn--d1abbgf6aiiy.xn--p1ai