Try disabling some of the repositories until you find the one that is being flaky. Sometimes they are offline and it messes things up.

The Wiki's on MAEMO.ORG have good stuff on xterm. I installed dropbear ssh to get to root and the password for that is rootme. You can change it from there.

Otherwise you can read some things in the WIKI's that will help with gaining root. You need to enable R&D mode for xterm to be able to do root or modify a script.

There are also good repository lists on maemo.org too.