Single Directory

I have a current Dolphin Site as my base site (www.bigangler.com) With existing users.

I added phpmydirectory to it the other day (http://bigangler.com/directory/) I need to have the phpmydirectory directory use the Dolphin db for authentication or have them integrated. There are no user account in the phpmydirectory currently
http://www.phpmydirectory.com

I added a wiki script to my site (http://bigangler.com/wiki/index.php5?title=Main_Page) It too has a directory and I want to use the Dolphin db for authentication or have them integrated. There are no user account in the Wikipedia currently
http://www.mediawiki.org/wiki/Installation

Both of these are php based and all reside on the same server so this should be possible fairly easily for a php programmer.

My goal is to have one user directory. If I have to have all users register through Dolphin than that is fine. Probably prefer it that way.

Please let me know if you can help.