Pear Auth Class (Newbie)

Does anyone have any working examples of the Pear Auth Class. I'm a bit of a beginner with PHP, especially Classes. I would like to use the Auth Class to give users access to secure areas of my site, but this would be based on group permissions. I have a permissions table with a column for each page of my site. Then I have one row for each group, and a "yes" or "no" in each field under the appropriate column to say whether they have permission to that page or not. I also use a separate table called TBLAuth where I keep username, password, group (for the permissions table), etc. So when a user logs onto my site, the auth system will check their permissions and direct them to the appropriate home page. And as they browse through the site, each page will check that they have the right user level (group) permission to proceed, or "ACCESS DENIED" type of thing. Does this make sense? Has anyone done something like this with the Pear Auth system, or is it even possible yet? If this is the wrong place to ask this kinda question, can someone please direct me to the right one. BTW, my intentions are to make as full use of the Pear stuff as possible. I will definitely be using Pear DB, and the Table class so far, most likely a lot more. Thanks for your help Simon