Problem with UML Composition

[Felix Natter <fnatter gmx net>]

hello,

I am trying to create a composition (strong aggregation)
between two classes in UML Diagram in dia 0.97.1.

I added a UML-Association and selected "Composition", but
there is no diamond on either side, as I think there should
be.
Please see the following screenshot:
http://www2.inf.fh-brs.de/~fnatte2s/uml_composition.png

Thanks,
-- 
Felix Natter