To allow AD users to be able to use things like Wiki, Blog and Podcast Producer in OSX, clear text authentication must be turned on between AD and OSX as by default, some hash format is used.

$ sudo serveradmin settings teams:enableClearTextAuth  = yes
$ sudo serveradmin stop teams
$ sudo serveradmin start teams
$ sudo serveradmin stop web
$ sudo serveradmin start web

Note: This was required in 10.5. Might still be required in 10.6.