I think I'm supposed to warn you not to go to this website and to be very careful if you do, but ...

First, make sure you don't have anything called Xournal in your installed apps.

Open the catalogs listing in App Manager. Look through any catalogs called "maemo Extras" and disable any that aren't expressly for Chinook.

If you don't have a "maemo Extras" for Chinook, then, using your NIT, go to this website:
http://www.gronmayer.com/it/index.php

Search for Xournal and you'll find that it's in a single repository. Click to install that repository.

Now go to installable apps in App Mgr, and select Xournal. Install it.

Then -- and here's where I think I'm supposed to be responsible -- go back to your catalogs and Disable the Chinook repository and re-Enable the Diablo "maemo Extras" repository. You shouldn't have any Fremantly repositories among your catalogs at all.

EDIT: I just saw your other post. To disable Diablo repositories, in Application Manager, go to the menu: Tools >> Application Catalog and there you can select a catalog and then click the Edit button. Keep track of any edits you do there, so you can undo them.