Just in case anyone else gets the same error installing from latest maemo (when I tried to install it told me it couldn't due to python2.5 runtime not being installed), I couldn't find a package named python2.5-runtime in the application manager but after clicking on Utilities -> X Terminal and typing: root and then: apt-get install python2.5-runtime it installed and now I could install slidelock (you need to install rootsh from the application manager to do this).