Hildon Application Manager is the package manager that comes with Maemo. Check from the X-terminal if it is installed, no need for root rights here with Code: apt-cache policy rootsh Be patient, this command takes some time! You need some way to download rootsh, may that be some computer or your n900, may be from the download page here http://repository.maemo.org/extras/p..._1.5_armel.deb Transfer it to your N900 and click the package in your file manager to install it again via HAM.
apt-cache policy rootsh