LDAP worked successfully in 1.0.1 and broke after an upgrade to 1.1RC1. The debug log shows:

Started POST "/users/login" for 172.29.74.189 at Thu Jan 03 09:03:49 -0600 2013
Processing by UsersController#login as HTML
Parameters: {"utf8"=>"â", "commit"=>"Login »", "authenticity_token"=>"aXBshxH56isuxV0N1g2WxN6QSdbcT8mo8Dt0LHuL2lk=", "login"=>{"password"=>"[FILTERED]", "login"=>"jbaird"}}
Setting current user thread-local variable to nil
User Load (0.2ms) SELECT `users`.* FROM `users` WHERE `users`.`login` = 'jbaird' LIMIT 1
AuthSource Load (0.2ms) SELECT `auth_sources`.* FROM `auth_sources` WHERE `auth_sources`.`id` = 2 LIMIT 1
LDAP-Auth with User na\svcforeman
Search Result: 0
Search Message: Success
no DN
Failed to authenticate Josh Baird against LDAP-NA authentication source
invalid user
Setting current user thread-local variable to nil
Redirected to http://foreman.corp.domain.com/users/login
Completed 302 Found in 27ms

na\svcforeman has access to read and search the LDAP directory. A TCPDUMP shows a successful query/lookup:

LDAPMessage searchResDone(2) success [1 result]
searchResEntry(2) "CN=Baird\, Josh,OU=CRP,OU=People,DC=na,DC=domain,DC=lan"

However, the log is showsing "Search Result: 0"