20110602-merge-duplicate-tracklists.sql contains several clauses that use ORDER BY inside of array_agg():
SELECT array_agg(tracklist ORDER BY tracklist ASC) AS all_merge
ORDER BY inside 8.4 is not supported and anyone using 8.4 (minimum supported version) can't upgrade. Please investigate a workaround that does not use ORDER BY. I'm guessing we need to create more temporary tables to accomplish this.