Right, but shouldn't environment variables be set up in user's context? I would just have one or more central files that each user's login would source to get the required environment variables. You shouldn't have to change them at every login. That is, you would only need to change when you:

1. Install a new version, or
2. Move the software to a new location or new server.

and then you would just edit those central file(s) once.