GDK warning for external plugins

[Jani Monoses]

> 
> Gdk-WARNING **: gdkdrawable-x11.c:904 drawable is not a pixmap or window
> 
> I've tested several plugins and this seems to happen only with external
> plugins, not with internal plugins. What is also interesting, is that it
> only happens when new items are added. When the panel is started and
> loads the plugins according to its configuration, I don't get any of
> these messages. I'm using xfce4-panel r19638. Does anyone (Jasper?) has
> any idea what could it possible be?

Same here, with the addition that external plugins (mailwatch, mixer) do 
not seem to launch their configure dialogs on being added to the panel. 
It happened only once out of several tries, which makes it even weirder.

Jani