diff -urN redmine-1.0.2/lib/redmine/wiki_formatting.rb redmine-1.0.2.new/lib/redmine/wiki_formatting.rb
--- redmine-1.0.2/lib/redmine/wiki_formatting.rb	2010-02-17 22:47:50.000000000 +0200
+++ redmine-1.0.2.new/lib/redmine/wiki_formatting.rb	2010-10-12 21:57:19.754024785 +0300
@@ -15,6 +15,8 @@
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
+require 'digest/md5'
+
 module Redmine
   module WikiFormatting
     @@formatters = {}
@@ -44,21 +46,30 @@
       end
       
       def to_html(format, text, options = {}, &block)
-        text = if Setting.cache_formatted_text? && text.size > 2.kilobyte && cache_store && cache_key = cache_key_for(format, options[:object], options[:attribute])
-          # Text retrieved from the cache store may be frozen
-          # We need to dup it so we can do in-place substitutions with gsub!
+        text, macros_grabbed = if Setting.cache_formatted_text? && text.size > 2.kilobyte && cache_store && cache_key = cache_key_for(format, options[:object], options[:attribute])
           cache_store.fetch cache_key do
-            formatter_for(format).new(text).to_html
-          end.dup
+            format_text(format, text)
+          end
         else
-          formatter_for(format).new(text).to_html
+          format_text(format, text)
         end
+
+        # Text retrieved from the cache store may be frozen
+        # We need to dup it so we can do in-place substitutions with gsub!
+	text = text.dup
+
         if block_given?
-          execute_macros(text, block)
+          execute_macros(text, macros_grabbed, block)
         end
         text
       end
 
+      def format_text(format, text)
+	text, macros_grabbed = preprocess_macros(text)
+	formatter = formatter_for(format).new(text)
+	[formatter.to_html, macros_grabbed]
+      end
+
       # Returns a cache key for the given text +format+, +object+ and +attribute+ or nil if no caching should be done
       def cache_key_for(format, object, attribute)
         if object && attribute && !object.new_record? && object.respond_to?(:updated_on) && !format.blank?
@@ -76,16 +87,38 @@
                     (
                     \{\{                        # opening tag
                     ([\w]+)                     # macro name
-                    (\(([^\}]*)\))?             # optional arguments
+                    (\((.*?)\))?                # optional arguments
                     \}\}                        # closing tag
                     )
-                  /x unless const_defined?(:MACROS_RE)
+                  /xm unless const_defined?(:MACROS_RE)
       
       # Macros substitution
-      def execute_macros(text, macros_runner)
+      
+      # Extract and store raw text for wiki_external_filter macro
+      # to avoid it being processed by the wiki engine
+      def preprocess_macros(text)
+        macros_grabbed = {}
+        text = text.gsub(MACROS_RE) do |s|
+	  esc, all, macro = $1, $2, $3.downcase
+	  if esc.nil? and (WikiExternalFilterHelper.has_macro macro rescue false)
+	    args = $5
+	    key = Digest::MD5.hexdigest("#{macro}:#{args}")
+	    macros_grabbed[key] = {:macro => macro, :args => args}
+	    "{{_macros_grabbed(#{key})}}"
+	  else
+	    s
+	  end
+	end
+	[text, macros_grabbed]
+      end
+
+      def execute_macros(text, macros_grabbed, macros_runner)
         text.gsub!(MACROS_RE) do
           esc, all, macro = $1, $2, $3.downcase
           args = ($5 || '').split(',').each(&:strip)
+	  if macro == '_macros_grabbed' and macros_grabbed.member? args.first
+	    macro, args = macros_grabbed[args.first].values_at(:macro, :args)
+	  end
           if esc.nil?
             begin
               macros_runner.call(macro, args)