I would say yes as an implement, but no as a weapon.
i mean if 10 foot pole was an implement, I wouldn't be able to use it as a weapon but I could cast spells through it.
Heck the small wizard could hold the staff erect on the ground, have the magic energy shoot up his arm, up the staff, and shoot out from the top of the staff at the bad guys. Swinging the staff like Robin Hood and Little John on the Bridge is not necessary.
I agree; halflings lose out on swinging their staff as a weapon, but they can still channel magic through it.
A staff is a shaft of wood as tall or slightly taller than you are, sometimes crowned with a decorative crystal or some other arcane fetish. Fashioned either as a quarterstaff or a walking staff, it is... Unlike other implements, a staff also functions as a melee weapon...
What you can't do with any Wizard or Warlock implement is hold one in your offhand and utilize its powers, you must actually wield it, which basically means you only get the benefit of one implement at a time.