Can't select Acrobat Pro for update 8.1.2

Hi Everyone,

I'm fairly new to this forum, and so far I've found it helpful. I'm a graphic design student and recently got CS3 Design Premium. I'm running OSX Leopard, and every time I try to update Acrobat Pro 8, the updater asks me to select my copy of Acrobat for update. The problem is, I go into Apps to select it, but it won't let me... it's grayed out. I can open the Acrobat folder, but I can't select the actual program. Is anyone else having this problem? Any suggestions would be appreciated.

Thanks!