When a character is wielding two melee weapons, he or she may choose to make a single attack roll with both weapons at a -2 Die Pool penalty. This attack deals damage equal to the total of the base damage of both weapons, plus 1/2 of the character’s Strength attribute.
You may also attack with one weapon and perform a combat trick with the other. The attacks are rolled separately, each with a -2 Die Pool penalty.
Using two weapons is otherwise the same as using only a single weapon.