Can Mathematica be made available to several users on a given machine?

I am collaborating with a colleague on a project for which we are using Mathematica. We currently have only one Mathematica license and we would love if we could both use it on the same machine, using different users.

Problem

When I try to open Mathematica (from Bash) with from my user account it works well but from my colleague's user account it is asking for the activation key.

/Applications/Mathematica.app/Contents/MacOS/MathKeel
Mathematica 10.0 for Mac OS X x86 (64-bit)
Copyright 1988-2014 Wolfram Research, Inc.

Mathematica caot find a valid password.

For automatic Web Activation enter your activation key
(enter retu to skip Web Activation): 

Question

Assume it is legal (which I am not quite sure yet), how can I indicate an "automatic password" on my colleagues user account so that it works from his account as it is currently working from mine?

FYI

The machine is ruing on MAC OS X 10.11.3. I own a student license (time unlimited) for desktop only (see short guidelines for Mathematica license types).