There’s another Acrobat security vulnerability today which can lead to system compromise if a user is directed to open a malicious PDF file.
Adobe has an update for Acrobat 8 already, but none yet for Acrobat 7 and they apparently plan none for previous versions. So if you forked out big bucks for Acrobat 6 Professional a couple years ago, they’re not going to support you, even though it’s their bug.
To address this and many future potential problems, go into your Acrobat preferences and disable Javascript. It’s right there in the left list in the preferences window. After all, it’s a document format, not an application platform.
Using alternate PDF viewers, most without JavaScript support, is another option.