I'm not sure what you're asking. If you are able to start IceWM and you are trying to run applications that need root user access (like Synaptic) from within IceWM, you're better to just run the programs from the Hildon menu or start the Debian chroot prompt (from OS2008) and run it from that command line. If you absolutely must run a root-user program from within IceWM, then your root password is the same as in OS2008. If you've never set your root password, you can install Maemo OpenSSH and it will ask you for a root password.