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Are you annoyed by bouncing icons in the Dock-and I'm not talking about the bounce when you open an application, but when a program wants to get your attention. Like when iChat has a video chat request, or System Preferences wants your OK to install a new panel, or Software Update found an update to install. The main problem I have with the bouncing icons is that they're never-ending; once they start, they won't stop until you switch to the application to end the bounce.
Even hiding the Dock doesn't seem to help, at least not all the time-when a Dock icon bounces with my Dock hidden at the bottom of the screen, it pops up just enough to be visible (and annoying). While some programs, such as iChat, nicely give you control over the dock bouncing, others provide no control at all.
If you dislike those bouncing icons, I have a fix. Unfortunately, it's an all-or-nothing proposition; you can't control bouncing on a per-application basis. But if you really dislike those bouncing icons, here's how to ground them forever. Open Terminal, in Applications -> Utilities, and enter these two commands (don't type the $; that's just the command prompt):
$ defaults write com.apple.dock no-bouncing -bool TRUE$ killall Dock
(If at some point you decide you'd rather have your bounce-happy Dock back, repeat the above commands, but change TRUE to FALSE at the end of the first command.)
The first command sets a hidden preference to stop all Dock icon bouncing, and the second command kills the Dock, which then restarts automatically. After it restarts, you'll never again be bothered by a bouncing application icon. This does mean, however, that it's now up to you to keep an eye on your running programs so that you know when one of them wants your attention.
Read article at Macworld.com