The package allows you to use the Ibycus 4 font for ancient Greek with Babel. It uses a Perl script to generate hyphenation patterns for Ibycus from those for the ordinary Babel encoding, cbgreek. It sets up ibycus as a pseudo-language you can specify in the normal Babel manner. For proper hyphenation of Greek quoted in mid-paragraph, you should use it with elatex (all current distributions of LaTeX are built with e-TeX, so the constraint should not be onerous).