Importing PHPBB3 Users and Posts


I am thinking of upgrading my PHPBB3 forum to this software, from searching I can see there is a tool to be able to import my database into this software BUT i cant seem to find it in the demo or in the resources page.

Could someone provide some more info into how this is done, where to find and the ease of importing. The main things i wish to keep from my current forums is Posts and User details (username, email, number of posts and maybe ranks / other custom fields)

Thanks for the help in advance