How should one invoke docker to take care of the PID 1 problem with zombie processes?

The phusion/baseimage boasts of taking care of the pid 1 problem with a light weight init process. How can one use the phusion/baseimage properly? I tried to invoke the image with the command ps aux shows ps running with a PID 1. What did I do wrong? What is the proper way to use the image? me@host:~/app1$ docker run --rm phusion/baseimage ps aux USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND root 1 3.0 0.0 29180 1404 ? Rs 01:27 0:00 ps aux