Merge branch 'stable' into rails31

doc-src/content/help/tutorials/configuration-reference.markdown

@@ -280,6 +280,13 @@ later on.
     <td style="vertical-align:top;">Symbol </td>
     <td style="vertical-align:top;">Defaults to <code>:chunky_png</code></td>
   </tr>
+  <tr>
+    <td style="vertical-align:top;"><code>chunky_png_options</code></td>
+    <td style="vertical-align:top;">Hash </td>
+    <td style="vertical-align:top;">
+      Defaults to <code>{:compression => Zlib::BEST_COMPRESSION}</code>. See the chunky_png <a href='https://github.com/wvanbergen/chunky_png/wiki/Constraints' _target='blank'>wiki</a> for more information
+    </td>
+  </tr>
 </table>
 
 <a name="configuration-functions"></a>

lib/compass/configuration.rb

@@ -38,7 +38,8 @@ module Compass
       :color_output,
       :preferred_syntax,
       :disable_warnings,
-      :sprite_engine
+      :sprite_engine,
+      :chunky_png_options
     ].flatten
 
     # Registers a new configuration property.

lib/compass/configuration/defaults.rb

@@ -133,6 +133,10 @@ module Compass
         :chunky_png
       end
       
+      def default_chunky_png_options
+        {:compression => Zlib::BEST_COMPRESSION}
+      end
+      
       # helper functions
 
       def http_join(*segments)

lib/compass/sass_extensions/sprites/engines/chunky_png_engine.rb

@@ -33,7 +33,8 @@ module Compass
           if canvas.nil?
             construct_sprite
           end
-          canvas.save(filename, :best_compression)
+          
+          canvas.save(filename,  Compass.configuration.chunky_png_options)
         end
         
       end