They are two repositories enabled: Community SSU and Maemo.org.
Disabled are Community SSU (testing), Community SSU (devil) and Community SSU (thump). The three Nokia repos not work. I've disabled them.
There isn't any "Extra" repository...? How can I include it?

I found this in the wiki:
The Extras repository is pre-configured on the N900 and listed as maemo.org and is enabled by default in PR1.1.

But maemo.org repo is enabled... And Modrana install failed...