common method is to go to a console, logging with an user then typing :
$ startx -- :1
but with slitaz I get :
╓
┊Fatal server error:
┊Setting default mixer volumes... Server is already active for display 0
┊ If this server is no longer running, remove /tmp/.X0-lock
┊ and start again.
╙
is it possible to run a second X session ? otherwise not a big deal, it's only for convenience coz I hacking a WM