So, I'm experimenting with a new search engine for the forum.
phpBB gives you two options and it turns out that the one on by default is the not as good but more compatable one. So I've moved us over to the fancier one as it works on our setup.
Apparently it's faster and more powerful, given that it appears to add a + sign onto queries it presumably has superior features too.
Please let me know if there are any problems with it as it seems rather good and has halved the size of our database by removing the cludgy version.