Animated Button?

[iPhoneCodeJunky]

So what I want to do is animate a button when I click it. Now, there are two types of animations. One is simple and I have done it, that is core animation type stuff. The other one is I want to replace the button image with another series of animated images.
I tried adding a UIImageView to the button and then soing a [imageView startAnimation] after my other animation (a core animation) was completed, but that actual image never shows up in the button at all.

Is my only option to replace my background image on my own? Is there a way to use the animation feature of a UIImageView within a button, or is there another way I should do it?
Thanks for your help...

[tawpie]

In EricaS's cookbook (this is not a plug, just a reference!!!) she has an example of exactly what you want to do. Except it requires a trick because you can't animate a button image. What she does is to make a semi-transparent button, then behind the button she makes a UIImageView that she animates in the "normal" fashion. Looks like a butterfly inside the button.