As far as I know, you cannot. You'll have to add your scripts in Acrobat after export.
I was able to merge the 2 worlds only in InDesign 5.0.3, Acrobat 8.0.0, Windows XP SP3. That is communicate with Acrobat from InDesign via BridgeTalk. Here is an example and here's a discussion on the InDesign scripting forum.
On the other hand, if you're on Mac, it's possible (I think so, but can't promise that it would work until I test it) to run JS (in Acrobat) from AS (InDesign or any scriptable application) via do script command.
Keith Gilbert talks about button tool tips here.
There is a script that quickly creates these buttons here.