javadoc:aggregate project filter

Hi,

I'd like to create API documentation for an eclipse RCP project.
Therefore I use the javadoc:aggregate goal which nicely builds
documentation for all my projects.

Now I want to filter some of them. When building with tycho junit tests
are typically kept in a separate project. Still the package names for a
test class ae the same as for the main class. This seems to be the best
practice approach right now.

Currently API documentation for test classes is built too. Is there a
way to filter a whole project from the aggregation step?

The only other approach I found was to use the javadoc:javadoc goal and
to manually add paths using the sourcepath parameter. For a big project
this is an error prone task which I would like to avoid.

regards
Christian