I haven't had time to try the latest snapshot yet. Will do tomorrow.

The algorithm of the greek lucene stemmer can be found as js here:
http://people.dsv.su.se/~hercules/greek_stemmer.gr.html
The logic seems quite simplistic 7step regex processing.

My vote would be the lucene libraries too.
They would provide a middle-ground between performance and feature-completeness
and if the integration was kept up to date with the latest version any new languages
would be 'free' feature upgrades for basex. The language coverage seems to be quite
extensive already.

alex