diff --git a/lib/redmine/plugin.rb b/lib/redmine/plugin.rb
index 9f2862c53..f2800d211 100644
--- a/lib/redmine/plugin.rb
+++ b/lib/redmine/plugin.rb
@@ -113,6 +113,12 @@ module Redmine #:nodoc:
       @registered_plugins = {}
     end
 
+    # Removes a plugin from the registered plugins
+    # It doesn't unload the plugin
+    def self.unregister(id)
+      @registered_plugins.delete(id)
+    end
+
     # Checks if a plugin is installed
     #
     # @param [String] id name of the plugin
diff --git a/test/functional/settings_controller_test.rb b/test/functional/settings_controller_test.rb
index fc64f87dc..80d3123a0 100644
--- a/test/functional/settings_controller_test.rb
+++ b/test/functional/settings_controller_test.rb
@@ -148,7 +148,8 @@ class SettingsControllerTest < ActionController::TestCase
     assert_tag 'form', :attributes => {:action => '/settings/plugin/foo'},
       :descendant => {:tag => 'input', :attributes => {:name => 'settings[sample_setting]', :value => 'Plugin setting value'}}
 
-    Redmine::Plugin.clear
+  ensure
+    Redmine::Plugin.unregister(:foo)
   end
 
   def test_get_invalid_plugin_settings
@@ -162,7 +163,8 @@ class SettingsControllerTest < ActionController::TestCase
     get :plugin, :id => 'foo'
     assert_response 404
 
-    Redmine::Plugin.clear
+  ensure
+    Redmine::Plugin.unregister(:foo)
   end
 
   def test_post_plugin_settings
@@ -181,6 +183,7 @@ class SettingsControllerTest < ActionController::TestCase
     post :plugin, :id => 'foo', :settings => {'sample_setting' => 'Value'}
     assert_response 404
 
-    Redmine::Plugin.clear
+  ensure
+    Redmine::Plugin.unregister(:foo)
   end
 end