So do you mean to say the other Gemini subprojects (e.g. Gemini JPA) are not available from there? Why not just deploy them all to the same repo?
Better still, while not deploy the whole lot to Maven Central? In the last few years, it has become rather a pain that everyone is running their own repositories. One-stop shopping at Maven Central is a lot easier for your artifact consumers.
The maven repo you are referring to is a SpringSource repo and is not an appropriate place for all of our Gemini project downloads. Shared repos of different types from the Eclipse domain servers will provide those who want to access either Maven or P2 repos to be able to obtain subproject downloads of all of the Gemini components.
The overhead of pushing to Maven Central might be an option if/when consumer demand justifies it.