During the process of adding an applet to the panel there is a whole whack of
CORBA stuff that needs to happen in order.  If any one of these things fails
then the panel destroys what it has done so far and presents a message like:

--------------------------------------------------------------------------
The panel encountered a problem while loading "OAFIID:GNOME_MixerApplet".
Do you want to delete the applet from your configuration?

                 [ Don't Delete ]  [ Delete ]
--------------------------------------------------------------------------

Half way through all of this CORBA stuff, ORBit_small_listen_for_broken is
called to register the dialog that pops up when the applet normally quits (ie:
not the one above, but rather, this one:)

-------------------------------------------------------
     "Volume Control" has quit unexpectedly

If you reload a panel object, i twill automatically
be added back to the panel.
      [ Don't Reload ]  [ Reload ]
-------------------------------------------------------

If an applet you're loading gets far enough to have this dialog registered but
doesn't make it all the way (ie: fails one of the checks after the dialog is
registered) then you get two error dialogs (one spawned by ORBit, and one
invokved manually from the failure-check code).

In addition to this, because of the cleanup that is done by the failure-check
code, the 'data' pointer for the response callback on the second dialog now
points to something that has been free'd (and causes the panel to crash about
20-30% of the time).

To test: run the mixer applet with environment G_DEBUG="fatal_warnings".  The
mixer applet (current CVS HEAD) emits a warning message while the panel is in
the part of the code that will cause the two dialogs to be thrown.