"Unaware ignores other Pokémon's positive and negative stat changes when calculating damage involving a Pokémon with this Ability. This means that damage dealt by a Pokémon with Unaware ignores the target's Defense and Special Defense stat changes. Likewise, damage dealt to a Pokémon with Unaware ignores the attacker's Attack and Special Attack stat changes."
http://bulbapedia.bulbagarden.net/wiki/Unaware_(Ability)
So yes Pokemon with unware will be unware that the Pokemon has a negative or postive stat change.
