diff --git a/app/views/users/index.api.rsb b/app/views/users/index.api.rsb
index 4265a4be4..4e898f4de 100644
--- a/app/views/users/index.api.rsb
+++ b/app/views/users/index.api.rsb
@@ -8,6 +8,7 @@ api.array :users, api_meta(:total_count => @user_count, :offset => @offset, :lim
       api.mail       user.mail
       api.created_on user.created_on
       api.last_login_on user.last_login_on
+      api.auth_source_id user.auth_source_id
 
       render_api_custom_values user.visible_custom_field_values, api
     end
diff --git a/app/views/users/show.api.rsb b/app/views/users/show.api.rsb
index e4c49f9b8..59452037d 100644
--- a/app/views/users/show.api.rsb
+++ b/app/views/users/show.api.rsb
@@ -8,6 +8,7 @@ api.user do
   api.last_login_on @user.last_login_on
   api.api_key    @user.api_key if User.current.admin? || (User.current == @user)
   api.status     @user.status if User.current.admin?
+  api.auth_source_id @user.auth_source_id if User.current.admin?
 
   render_api_custom_values @user.visible_custom_field_values, api

diff --git a/test/fixtures/users.yml b/test/fixtures/users.yml
index 986ed5d67..da1241206 100644
--- a/test/fixtures/users.yml
+++ b/test/fixtures/users.yml
@@ -148,6 +148,21 @@ users_009:
   mail_notification: only_my_events
   login: miscuser9
   type: User
+users_014:
+  id: 14
+  created_on: 2006-07-19 19:33:19 +02:00
+  status: 1
+  last_login_on:
+  language: 'de'
+  hashed_password: 1
+  updated_on: 2006-07-19 19:33:19 +02:00
+  admin: false
+  lastname: Ldap
+  firstname: User
+  auth_source_id: 1
+  mail_notification: only_my_events
+  login: ldapuser
+  type: User
 groups_010: 
   id: 10
   lastname: A Team
diff --git a/test/functional/auth_sources_controller_test.rb b/test/functional/auth_sources_controller_test.rb
index e6bfcf54c..b45ad7b57 100644
--- a/test/functional/auth_sources_controller_test.rb
+++ b/test/functional/auth_sources_controller_test.rb
@@ -142,7 +142,8 @@ class AuthSourcesControllerTest < Redmine::ControllerTest
     assert_select_error /host cannot be blank/i
   end
 
-  def test_destroy
+  def test_destroy_auth_source_not_in_use
+    User.find(14).update_attribute :auth_source_id, nil
     assert_difference 'AuthSourceLdap.count', -1 do
       delete :destroy, :params => {
           :id => 1
diff --git a/test/integration/api_test/users_test.rb b/test/integration/api_test/users_test.rb
index 468caf398..c02191c87 100644
--- a/test/integration/api_test/users_test.rb
+++ b/test/integration/api_test/users_test.rb
@@ -28,6 +28,18 @@ class Redmine::ApiTest::UsersTest < Redmine::ApiTest::Base
     assert_select 'users' do
       assert_select 'user', User.active.count
     end
+    assert_select 'users user' do
+      assert_select 'id', User.active.count
+      assert_select 'login', User.active.count
+      assert_select 'firstname', User.active.count
+      assert_select 'lastname', User.active.count
+      assert_select 'mail', User.active.count
+      assert_select 'created_on', User.active.count
+      assert_select 'last_login_on', User.active.count
+      assert_select 'auth_source_id', User.active.count
+      assert_select 'auth_source_id', ""
+      assert_select 'auth_source_id', "1"
+    end
   end
 
   test "GET /users.json should return users" do
@@ -125,6 +137,18 @@ class Redmine::ApiTest::UsersTest < Redmine::ApiTest::Base
     assert_select 'user status', :text => User.find(1).status.to_s
   end
 
+  test "GET /users/:id should not return auth_source_id for standard user" do
+    get '/users/14.xml', :headers => credentials('jsmith')
+    assert_response :success
+    assert_select 'user auth_source_id', 0
+  end
+
+  test "GET /users/:id should return auth_source_id for administrators" do
+    get '/users/14.xml', :headers => credentials('admin')
+    assert_response :success
+    assert_select 'user auth_source_id', :text => '1'
+  end
+
   test "POST /users.xml with valid parameters should create the user" do
     assert_difference('User.count') do
       post '/users.xml',