The first hurdle of installing MovableType beta4 is that the download page does some fancy redirection to push the download to your browser which is not helpful if you have disabled ftp upload up to your dreamhost website and want to download it via wget from within a shell. However there are a couple of sites that point to a direct location that was made public when the beta was first released so you can get it (for now) from sippey. There is a nice tutorial on installing MT4 on dreamhost