AutoRefresher is a plugin for eclipse that implements automatic refreshing of file resources for Mac OS X using system events (through the NativeFSEvents library). The plugin replaces the default filesystem polling used by eclipse on these operating systems.
Download the bundle from http://vaadin.com/addon/autorefresher and copy the contents of the plugins directory to your eclipse/dropins/ directory.
Start eclipse and open Preferences -> General -> Workspace and check the "Refresh using native hooks or polling" checkbox.
Enjoy!