One requirement would be that it runs on Windows. Is that something you have tested?If there is interest - I'm sure Nathan and I would be willing to put it on pgfoundry, and at some point give it up for inclusion into PostgreSQL.
In case it influences anyone, MySQL 5 already has built-in UUID support: http://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#id2899901 Chris