Shifting/fluid navigation bar

Hi all.
I’m trying to achieve something like this and have no idea where to begin. I’m relatively new to flash, here’s my scenario.

navbar has

A|B|C|D

click on C bar slides and you get

C|A|B|D

click on D bar slides and you get

D|A|B|C and so on.

Help or a link to help is much appreciated.

any ideas?

I’ve tried some different things with linking buttons to partial animations inside movieclips but i think i’m totally off base. Any ideas.