I have posted just to give marco my opinion of Snitz forums and am NOT trying to poach members!
I am running Snitz Forums software, which I find is excellent and doesn't attract ANY of these fake ID's trying to sign up to use your forum. If the system does detect anyone trying to do this (ie repeated attempts) it blocks that user for trying to register on your forum and records its actions in the control panel- from there you can delete or allow the user to use the forum.
I cannot reiterate how good the Snitz forum software is and it would be easy to implement Snitz by transferring all the data from phpBB to Sniz using a .csv file.
Hope I am of help
James