Right, but they use the same proficiency as scimitars, don't they? I suppose I should have worded it better - I meant new weapon types that didn't have a preexisting proficiency in BG1 when I mentioned katana.
I thought that I'd played a game of BG before getting TotSC installed at one point, but I know that Winthrop has always had scimitars available... OTOH, that explains the dearth of magical scimitars until really late in the game (unless you kill Drizzt)...