Software Deployment

For my company I must distribute the SMS Admin Console 2003. I have created a msi package with the setup files and a custom action to start the installation. Command that I use is \bin\i386\setup.exe /script admin.ini /NoUserInput. This works just fine. But how can I deinstall the package unattended? Is there an (hidden) switch like setup.exe /x (doesn't work, checked)?? Or is it something in the admin.ini?

[Identification]
Action = InstallAdminUI <- Deinstall/uninstall does not work.

Any ideas?