If I have the Aptana icon saved in the Dock, when I launch it, a second aptana icon appears in the Dock with the name "java" this is the actual application icon. If I save that new icon to the Dock, then the icon turns generic when aptana is not running. It turns back to the aptana icon when it's running. This is related to
STU-151
This used to happen years ago with Eclipse 2.x and OS X 10.3/10.4