[eluser]Vheissu[/eluser]
We don't need a fully fledged ACL system, we have Zend_Acl for that. However, what I did in my auth library is create a role based type ACL set up. You can restrict controllers and functions to specific users and role ID's to have an ACL kind of set up. Of course, you can't define a list of access, but I'm going to have a config file set up and let you specify an argument to make the restrict functions use config values (look up controller / function name).
Maybe you can employ something similar in your library? Just a suggestion.