Getting Simultaneous-Use users to share bandwidth

Hello, I am using freeradius-server-2.1.0 and have an issue that I need help with. I have a Simultaneous-Use attribute set in radcheck table to 5 to allow for that number of users sharing one username. I have also set WISPr-Bandwidth-Max-Down and WISPr-Bandwidth-Max-Up to 2048000 to cap data usage to that much. However I note is that each simultaneous user is allowed the entire 2048000 bandwidth. How can I configure the server to have all simultaneous users with the same username limited to the same WISPr-Bandwidth-Max-Up/Down value (2048000 in my case)? Thanks.