There is no way for you to recover the information in the damaged cards. But you might be able to discard the damaged cards and create a new stack that works properly.
Two years ago, Apple Computer released a simple utility, named Recover, that lets you try to salvage the good cards in the stack. It works by copying cards one by one into a new stack, and skipping bad cards.
This utility is available from GEnie, CompuServe, and user groups.
This article is adapted from the Claris Tech Info database.