Rewrite Question

[lightwave]

I used to have phpbb and google index about about 17,000 of my topics.

To view a topic in phpbb, its viewtopic.php?t={topic number}

Well, when I imported, I still have the original import ids of the converted topics.

can anybody help me with a rewrite where when someone accesses viewtopic.php?t={topic number} it executes a query from the database to find which current vbulletin topic has an import id that matches the $t.

then it goes to the NEW VBULLETIN topic id that is showthread.php?t={topic number}