Please do not lock Jobs to the Weapon Class that unlocks them.

[Chinook]

I'd like to point out that jobs being specialized has no effect on what weapon you can equip.

Well we don't know yet ... As Dargoth pointed out from the 10th letter, they might make some weapons job-specific (X sword being Warrior exclusive for example or a new weapon type only available to Y job being a variant of the weapon used by the base class).