Unloading my plugin from another process

I'm toying with adding an NSDockTilePlugIn to my application, but I've come across some strange behavior -- understandable behavior, but I'd like to see if there is a way around it.

When I run my app from the dmg or keep the (dmg version of the) app in the Dock, the Dock loads my .docktileplugin bundle.

When the application quits, the plugin receives a setDockTile: messa开发者_如何学Goge with a nil NSDockTile * (as per the documentation). However, the plugin keeps running, and I cannot eject (unmount, detach) the dmg unless I kill the Dock (I suppose logging out would work too).

I've tried sending a Notification through the NSDistributedNotificaitonCenter (from a non-dmg version of the app) to tell it to unload, but the Console tells me that now I have two of the same docktileplugin loaded, and it is undefined which one will execute.

And even though [[NSBundle bundleWithPath:...] unload] returns YES, I still cannot eject the dmg.