The rules for "Pro Line4" (all variants) are the same as the respective rule for the standard Line4 variant except that 5-in-a-row does not make a win.
If I and Jason were playing "Pro Linetris", this game wouldn't have already ended (and I might win it too).
hexkid: I've never heard of this Pro Line4 being played anywhere. Incidentally, in that game you linked to, I note that Jason does have a diagonal four in a row in addition to the horizontal five in a row.