Improved Unarmed Strike and Natural Attacks

[Mockingbird]

I've been hearing a lot about the IUS feat giving Natural attacks iteratives, but where is this printed in Pathfinder? I use a lot of Natural attacks and am trying to maximize damage with them (3d6 +8 in a full attack action at 6th level, meh.)
The DM doesn't usually allow things that aren't printed, so where does it say this?

[Keld Denar]

No. You have it wrong. IUAS can give you your iteratives ON TOP of your natural attacks.

You can only make one natural attack per limb. Holding a weapon gives you iterative attacks. If you are holding a weapon to get iterative attacks, though, you aren't using that natural weapon.

IUAS gets around that. You don't have to hold a weapon, your body is the weapon. Thus, you can make your full compliment of iterative attacks with your UAS, then make all of your natural attacks as secondaries. You get the best of both worlds. Really great if your have a non-Str form of bonus damage like Sneak Attack, Chaos Incarnate Radiance, or Knowledge Devotion.

I don't really know how this changes with Pathfinder, though, if thats where your question lies. I'm more of a 3.5 kinda guy.

My mini-guide about Natural Weapons. (http://brilliantgameologists.com/boards/index.php?topic=10994.0)

[Starbuck_II]

I've been hearing a lot about the IUS feat giving Natural attacks iteratives, but where is this printed in Pathfinder? I use a lot of Natural attacks and am trying to maximize damage with them (3d6 +8 in a full attack action at 6th level, meh.)
The DM doesn't usually allow things that aren't printed, so where does it say this?

Well, you can flurry with it in PF.
http://www.d20pfsrd.com/feats/combat-feats/feral-combat-training-combat

But nothing allows Iteratives with it in Pathfinder.