Testing Foreman with FreeIPA as LDAP Auth Source (with onthefly_register enabled), user has a unicode surname (full user name: Robert Křižovatka).
When logging as this user in Foreman Web UI, it fails with "incorrect username or pasword".

Traceback from production log:

2015-07-27 06:59:21 [app] [I] 
 | 
 | Started POST "/users/login" for 2620:52:0:2282:6af7:28ff:fec1:b34b at 2015-07-27 06:59:21 -0400
2015-07-27 06:59:21 [app] [I] Processing by UsersController#login as HTML
2015-07-27 06:59:21 [app] [I]   Parameters: {"utf8"=>"✓", "authenticity_token"=>"Q44WOQeP5w9y2fpAWCTLb4fveAYRxCmvag5qHZjewyE=", "login"=>{"login"=>"bob17432", "password"=>"[FILTERED]"}, "commit"=>"Login"}
2015-07-27 06:59:21 [app] [D] Setting current user thread-local variable to nil
2015-07-27 06:59:21 [sql] [D]   User Load (0.7ms)  SELECT "users".* FROM "users" WHERE "users"."lower_login" = 'bob17432' LIMIT 1
2015-07-27 06:59:21 [sql] [D] Attempting to log into an auth source as bob17432 for account auto-creation
2015-07-27 06:59:21 [sql] [D]   AuthSource Load (0.5ms)  SELECT "auth_sources".* FROM "auth_sources" WHERE "auth_sources"."onthefly_register" = 't'
2015-07-27 06:59:21 [sql] [D] Authenticating 'bob17432' against 'LDAP-ipa-ldap-test7432'
2015-07-27 06:59:21 [sql] [D] LDAP auth with user bob17432 against LDAP-ipa-ldap-test7432
2015-07-27 06:59:21 [sql] [I] Successfully decrypted field for AuthSourceLdap ipa-ldap-test7432
2015-07-27 06:59:21 [sql] [D] Retrieved LDAP Attributes for bob17432: {:firstname=>"Robert", :lastname=>"K\xC5\x99i\xC5\xBEovatka", :mail=>"bob17432@domain.com", :dn=>"uid=bob17432,cn=users,cn=accounts,dc=realm,dc=com"}
2015-07-27 06:59:21 [sql] [D] Authentication successful for 'bob17432'
2015-07-27 06:59:21 [sql] [D]   User Load (0.7ms)  SELECT "users".* FROM "users" WHERE "users"."lower_login" = 'foreman_admin' LIMIT 1
2015-07-27 06:59:21 [app] [D] Setting current user thread-local variable to foreman_admin
2015-07-27 06:59:21 [sql] [D]    (0.1ms)  BEGIN
2015-07-27 06:59:21 [sql] [D]   User Exists (0.6ms)  SELECT 1 AS one FROM "users" WHERE LOWER("users"."login") = LOWER('bob17432') LIMIT 1
2015-07-27 06:59:21 [sql] [D]   AuthSource Load (0.6ms)  SELECT "auth_sources".* FROM "auth_sources" WHERE "auth_sources"."id" = 13 LIMIT 1
2015-07-27 06:59:21 [sql] [D]    (0.5ms)  SELECT COUNT(*) FROM "usergroups" WHERE "usergroups"."name" = 'bob17432'
2015-07-27 06:59:21 [sql] [D]    (0.8ms)  SELECT "roles".id FROM "roles" INNER JOIN "user_roles" ON "roles"."id" = "user_roles"."role_id" WHERE "user_roles"."owner_id" IS NULL AND "user_roles"."owner_type" = 'User'
2015-07-27 06:59:21 [sql] [D]    (0.2ms)  ROLLBACK
2015-07-27 06:59:21 [sql] [I] Failed to save User 'bob17432' ["Surname is invalid"]
2015-07-27 06:59:21 [app] [D] Setting current user thread-local variable to nil
2015-07-27 06:59:21 [sql] [I] invalid user
2015-07-27 06:59:21 [app] [D] Setting current user thread-local variable to nil
2015-07-27 06:59:21 [app] [I] Redirected to https://dell-pe1850-04.rhts.eng.bos.redhat.com/users/login
2015-07-27 06:59:21 [app] [I] Completed 302 Found in 124ms (ActiveRecord: 30.1ms)

rpm -qf /usr/share/foreman-installer/modules/foreman/lib/facter/sssd.rb /usr/share/foreman-installer/modules/foreman/lib/facter/util/sssd.rb
foreman-installer-1.10.0-0.develop.201507210324gitb34c05c.el7.noarch
foreman-installer-1.10.0-0.develop.201507210324gitb34c05c.el7.noarch