It will change to a class specific one.
This will be the pattern for it.
Taken from the DQ Wiki just go to the bottom page or search Jasper
Item Conversions (Jasper)
MainHand
Wizard Warrior Rogue
Staff Sword Chakram
Wand Lance Flintlock
Sword Hammer Dagger
Gauntlet Axe Bow
OffHand
Wizard Warrior Rogue
Manashield Hatchet Mirror
Skull Horn Trap
Tome Totem Vial
Orb Shield Bomb