--- init.rb	2014-03-05 20:53:07.000000000 -0600
+++ init.rb	2014-03-10 13:47:13.000000000 -0500
@@ -6,31 +6,49 @@
 		base.send(:include, InstanceMethods)
 
 		base.class_eval do
-		  alias_method_chain :custom_fields_tabs, :wktime_tab
+          if Redmine::VERSION::MAJOR >= 2 && Redmine::VERSION::MINOR >= 5
+            alias_method_chain :render_custom_fields_tabs, :render_wktime_tab
+            alias_method_chain :custom_field_type_options, :wktime_tab_options
+          else
+            alias_method_chain :custom_fields_tabs, :wktime_tab
+          end
 		end
 	end
 
 	module InstanceMethods
 		# Adds a wktime tab to the custom fields administration page
 		def custom_fields_tabs_with_wktime_tab
-			tabs = custom_fields_tabs_without_wktime_tab
-			# Code added to check if the tab already exist - to fix the multiple tab issue
-			appendTab = true
-			tabs.each do |tab|
-				if tab[:name].eql? 'WktimeCustomField'
-					appendTab = false
-					break
-				end
-			end
-			if appendTab			
-				tabs << {:name => 'WktimeCustomField', :partial => 'custom_fields/index', :label => :label_wk_time}
-			end
-			return tabs
+			add_wktime_cf
+			custom_fields_tabs_without_wktime_tab
 		end
+		
+        def render_custom_fields_tabs_with_render_wktime_tab(types)          
+          add_wktime_cf
+          render_custom_fields_tabs_without_render_wktime_tab(types)
+        end
+
+        def custom_field_type_options_with_wktime_tab_options          
+          add_wktime_cf
+          custom_field_type_options_without_wktime_tab_options
+        end                                
+           
+		private
+        
+        def add_wktime_cf
+          cf = {:name => 'WktimeCustomField', :partial => 'custom_fields/index', :label => :label_wk_time}
+          unless CustomFieldsHelper::CUSTOM_FIELDS_TABS.index { |f| f[:name] == cf[:name] }
+            CustomFieldsHelper::CUSTOM_FIELDS_TABS << cf 
+          end 
+        end
 	end
 end
 
-CustomFieldsHelper.send(:include, WktimeHelperPatch)
+# Apply patch
+Rails.configuration.to_prepare do
+  unless CustomFieldsHelper.included_modules.include?(WktimeHelperPatch)
+    CustomFieldsHelper.send(:include, WktimeHelperPatch)
+  end
+end
 
 Redmine::Plugin.register :redmine_wktime do
   name 'Time & Expense'