You can do it yourself if you’ve got the knowledge (or are willing to acquire it), otherwise it’ll have to wait until someone else who does have the knowledge bumps into the problem (or is pointed in the appropriate direction and told “go forth and fix”). We (CDCK) do phpBB imports every now and then, so if this is a persistent problem we’ll end up fixing it if nobody does in the meantime. It wouldn’t surprise me, though, if you try it again tomorrow sometime, if it all Just Worked, and it was a temporary repo problem.