Extension Problem

["Felix Eisele" <felix_eisele gmx de>]

Hello together,
I writing a extension for F-spot.
And now I have the Problem that at the
startup of F-Spot this message is display:

Warning: The add-in "Fspot.exporter, 0.4.3.1" is trying to extend
'/Fspot/Menus/Exports',
But there isn't any compatible add-in defining this extension point'
 
The first time I start Fspot the Extension is installed but at the second
start the Extension
Don't show in the menu.
Can someone help me?

Greets Felix Eisele