Question concerning AoOs

[frogglesmash]

When you make an AoO does it have to be a normal attack, or can you use it to make attempt to disarm/trip/bullrush etc?

[flappeercraft]

When you make an AoO does it have to be a normal attack, or can you use it to make attempt to disarm/trip/bullrush etc?

Disarms, trips and bullrushes are all kinds of attacks which can be made instead of regular attacks whether on an AoO or Iterative attacks.

[Thurbane]

^ If you need a source to back this up, Rules Compendium states it unequivocally.