Swapping Symbols in Flash?

[Virt]

I have Flash CS3. I'm making an animation using lots an' lots of tweens. I converted one of the tweens to frame animation so I could do some symbol swapping (the frames are hand-animated and are being imported into flash,) but it's not allowing me to swap the symbols. It gives me the option to, but when I selected the image I wanted to swap to, it stayed the same. Any ideas as to how to work around it?

EDIT: Nevermind, found a way around it. I simply broke apart the symbol (restored it to a bitmap) and then swapped the bitmap. Easy!