diff --git a/lib/redmine/helpers/gantt.rb b/lib/redmine/helpers/gantt.rb
index 31956bfae..168ce43f7 100644
--- a/lib/redmine/helpers/gantt.rb
+++ b/lib/redmine/helpers/gantt.rb
@@ -400,7 +400,7 @@ module Redmine
             gc.stroke('transparent')
             gc.strokewidth(1)
             gc.draw('text %d,%d %s' % [
-              left.round + 8, 14, Redmine::Utils::Shell.shell_quote("#{month_f.year}-#{month_f.month}")
+              left.round + 8, 14, image_text_quote("#{month_f.year}-#{month_f.month}")
             ])
             left = left + width
             month_f = month_f >> 1
@@ -436,7 +436,7 @@ module Redmine
               gc.stroke('transparent')
               gc.strokewidth(1)
               gc.draw('text %d,%d %s' % [
-                left.round + 2, header_height + 14, Redmine::Utils::Shell.shell_quote(week_f.cweek.to_s)
+                left.round + 2, header_height + 14, image_text_quote(week_f.cweek.to_s)
               ])
               left = left + width
               week_f = week_f + 7
@@ -797,7 +797,7 @@ module Redmine
         params[:image].stroke('transparent')
         params[:image].strokewidth(1)
         params[:image].draw('text %d,%d %s' % [
-          params[:indent], params[:top] + 2, Redmine::Utils::Shell.shell_quote(subject)
+          params[:indent], params[:top] + 2, image_text_quote(subject)
         ])
       end
 
@@ -1040,10 +1040,18 @@ module Redmine
         if label
           params[:image].fill('black')
           params[:image].draw('text %d,%d %s' % [
-            params[:subject_width] + (coords[:bar_end] || 0) + 5, params[:top] + 1, Redmine::Utils::Shell.shell_quote(label)
+            params[:subject_width] + (coords[:bar_end] || 0) + 5, params[:top] + 1, image_text_quote(label)
           ])
         end
       end
+
+      def image_text_quote(text)
+        if Redmine::Platform.mswin?
+          %Q!"#{text.gsub(/(")/, '\\\\\1')}"!
+        else
+          %Q!'#{text.gsub(/(')/, '\\\\\1')}'!
+        end
+      end
     end
   end
 end
diff --git a/test/functional/gantts_controller_test.rb b/test/functional/gantts_controller_test.rb
index d89ae52db..1fa5126a2 100644
--- a/test/functional/gantts_controller_test.rb
+++ b/test/functional/gantts_controller_test.rb
@@ -170,6 +170,7 @@ class GanttsControllerTest < Redmine::ControllerTest
 
   if Object.const_defined?(:MiniMagick) && convert_installed?
     def test_gantt_should_export_to_png
+      Issue.generate!(:subject => %q!Subject containing special characters " and '!)
       get(
         :show,
         :params => {