As you probably have guessed from the title of this post, I am not happy with this behavior, so I have written a class, CLAlert (MIT License) that displays alerts the way I think it should be done. I.e. a note icon for an informational alert, a caution icon for a warning alert and a stop icon for a critical alert as you can see on these screenshots.
(tags: cocoa nsalert mitlicense opensource)
When you want to localize your application, you can take several routes.