diff --git a/app/models/project.rb b/app/models/project.rb
index 7ce0051ed..e4db6d867 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -287,10 +287,14 @@ class Project < ActiveRecord::Base
   end
   
   def enabled_module_names=(module_names)
-    enabled_modules.clear
-    module_names = [] unless module_names && module_names.is_a?(Array)
-    module_names.each do |name|
-      enabled_modules << EnabledModule.new(:name => name.to_s)
+    if module_names && module_names.is_a?(Array)
+      module_names = module_names.collect(&:to_s)
+      # remove disabled modules
+      enabled_modules.each {|mod| mod.destroy unless module_names.include?(mod.name)}
+      # add new modules
+      module_names.each {|name| enabled_modules << EnabledModule.new(:name => name)}
+    else
+      enabled_modules.clear
     end
   end
   
diff --git a/test/unit/project_test.rb b/test/unit/project_test.rb
index 94177f433..27cff13d6 100644
--- a/test/unit/project_test.rb
+++ b/test/unit/project_test.rb
@@ -18,7 +18,9 @@
 require File.dirname(__FILE__) + '/../test_helper'
 
 class ProjectTest < Test::Unit::TestCase
-  fixtures :projects, :issues, :issue_statuses, :journals, :journal_details, :users, :members, :roles, :projects_trackers, :trackers, :boards
+  fixtures :projects, :enabled_modules, 
+           :issues, :issue_statuses, :journals, :journal_details,
+           :users, :members, :roles, :projects_trackers, :trackers, :boards
 
   def setup
     @ecookbook = Project.find(1)
@@ -218,4 +220,17 @@ class ProjectTest < Test::Unit::TestCase
     Project.delete_all
     assert_nil Project.next_identifier
   end
+  
+  def test_enabled_module_names_should_not_recreate_enabled_modules
+    project = Project.find(1)
+    # Remove one module
+    modules = project.enabled_modules.slice(0..-2)
+    assert modules.any?
+    assert_difference 'EnabledModule.count', -1 do
+      project.enabled_module_names = modules.collect(&:name)
+    end
+    project.reload
+    # Ids should be preserved
+    assert_equal project.enabled_module_ids.sort, modules.collect(&:id).sort
+  end
 end