SQLite3 appears to come with three different full-text search engines, called FTS1, FTS2, and FTS3. The documentation available on the website mentions that FTS1 is stable, FTS2 is in development, and that you should use FTS2. Examples I find online use FTS3, which is in CVS, and not documented versus FTS2. None of the full-text search engines come with the amalgamated source, as near as I can tell.

So, my question: which of these three engines, if any, should I use for full-text indexing in SQLite? Or should I simply use a third-party tool like Sphinx, or a custom solution in Lucene, instead?