UBB.threads PHP Forum Software Community Forums UBB.threads 7 Importer Support Import UBB classic from to UBB threads runs on a new server

Wondering if it this plan is possible:

http://www.phpbb.com/community/viewtopic.php?t=7574

migration plan is the following
1- migrate from ubb classic to phpbb 2
2- then upgrade from phpbb 2 to phpbb3
3- convert phpbb3 to vb forums or what ever

Its a forum with a UBB classic 6.7.3 flavor and wanting to go to vBulletin.

Can the database let alone threads be converted?