Having looked at Zend_Acl, I found it to be lacking somewhat in terms of usability. Unless I am mistaken, you are only able to create access controls for specific types of pages, not granular down to specific resources.
Have not played with Tackle, but did look at phpGACL, and found it difficult to understand well enough to implement (not to mention lack of updates makes me think the project is dead).
I have been working on rolling my own ACL class, database driven, and granular with Roles, Groups, and Users, as there seems to be nothing in the tubes of the internet that I can find.
I would suggest either rolling your own, or waiting for the forever it seems to be taking me to complete mine. Or play with phpGACL. Good luck, and I hope there is a good answer to come out of this question.