Our university is looking for a secure way to sell/deliver software to our students and faculty online. The main focus is securely downloadable software (protected url's of some sort).

The basics needs are:
1. integrated LDAP pass through authentication (or CAS, siteminder, etc.).
2. Groups based inventory views (role will be associated with user, user can only see software assigned to that same role).
3. Easily support custom purchase options (department cards--CSV export, Student Cards--Web service, etc.).

Would Zen Cart be a good candidate or would would ya'll suggest another project or building our own?

Thanks.

D.