stormmedia: With the patch, Sephiroth has the Masamune in battle but that's just the model not the real one (in menu he has the swords of Cloud). So the modeling is already in, the only -last- thing to do is to create a special sword, for the weapon menu, like the one Sephiroth gots in the flashback (or using this one if it's possible).
Dark_Ansem: I'm maybe bad at searching information but I can't find from where you get yours.