Despite the line "no creature with an Intelligence score of 3 or higher can be an animal", it's possible to achieve it.
For example, before the change to Wildshape to base it off Alternate Form, a druid explicitly gained the Animal type while retaining his own Intelligence score. Even after those changes, the same effect occurs when using a Polymorph spell.
A simple question is "What happens when you cast Fox's Cunning on a dog?"
Would this result in a change in Type? I see no reason it should. I could see a rules-based justification for it granting a +4 enhancement bonus to Int (maximum 2), but not for changing the creature's Type.
My own inclination would be to let the spell result in an Animal with an Int of 5 or 6; I would not, however, allow Animal hit dice to increase Int above 2, just like Klaus.
javcs said:
Why not? What restricts the abilities that I could increase?
To me, "no creature with an Intelligence score of 3 or higher can be an animal" covers the question of "Can I, by virtue of being an Animal (ie, through gaining more hit dice of the Animal type) increase my Intelligence score to 3 or higher?"
If you're getting a +1 to an ability score by advancing in the Animal Type, that ability score increase is beholden to the rules of the Animal Type.
-Hyp.