diff --git a/lib/chunks/chunk.rb b/lib/chunks/chunk.rb
index 9ba3cc04..ad0fb148 100644
--- a/lib/chunks/chunk.rb
+++ b/lib/chunks/chunk.rb
@@ -27,8 +27,8 @@ module Chunk
 
     # a regexp that matches all chunk_types masks
     def Abstract::mask_re(chunk_types)
-      tmp = chunk_types.map{|klass| klass.mask_string}.join("|")
-      Regexp.new("chunk([0-9a-f]+n\\d+)(#{tmp})chunk")
+      chunk_classes = chunk_types.map{|klass| klass.mask_string}.join("|")
+      /chunk(\d+)(#{chunk_classes})chunk/
     end
     
     attr_reader :text, :unmask_text, :unmask_mode
@@ -53,14 +53,7 @@ module Chunk
 
     # should contain only [a-z0-9]
     def mask
-      @mask ||="chunk#{@id}#{self.class.mask_string}chunk"
-    end
-
-    # We should not use object_id because object_id is not guarantied 
-    # to be unique when we restart the wiki (new object ids can equal old ones
-    # that were restored from madeleine storage)  
-    def id
-      @id ||= "#{@content.page_id}n#{@content.chunk_id}"
+      @mask ||= "chunk#{self.object_id}#{self.class.mask_string}chunk"
     end
 
     def unmask
diff --git a/lib/wiki_content.rb b/lib/wiki_content.rb
index dcc89ef9..6fcc4a85 100644
--- a/lib/wiki_content.rb
+++ b/lib/wiki_content.rb
@@ -59,14 +59,14 @@ module ChunkManager
 
   def add_chunk(c)
       @chunks_by_type[c.class] << c
-      @chunks_by_id[c.id] = c
+      @chunks_by_id[c.object_id] = c
       @chunks << c
       @chunk_id += 1
   end
 
   def delete_chunk(c)
     @chunks_by_type[c.class].delete(c)
-    @chunks_by_id.delete(c.id)
+    @chunks_by_id.delete(c.object_id)
     @chunks.delete(c)
   end
 
@@ -82,18 +82,15 @@ module ChunkManager
     @chunks.select { |chunk| chunk.kind_of?(chunk_type) and chunk.rendered? }
   end
 
-  # for testing and WikiContentStub; we need a page_id even if we have no page
-  def page_id
-    0
-  end
-
 end
 
 # A simplified version of WikiContent. Useful to avoid recursion problems in 
 # WikiContent.new
 class WikiContentStub < String
+  
   attr_reader :options
   include ChunkManager
+  
   def initialize(content, options)
     super(content)
     @options = options
@@ -167,7 +164,7 @@ class WikiContent < String
     @options[:engine].apply_to(copy)
 
     copy.inside_chunks(HIDE_CHUNKS) do |id|
-      @chunks_by_id[id].revert
+      @chunks_by_id[id.to_i].revert
     end
   end
 
@@ -183,14 +180,16 @@ class WikiContent < String
     pre_render!
     @options[:engine].apply_to(self)
     # unmask in one go. $~[1] is the chunk id
-    gsub!(MASK_RE[ACTIVE_CHUNKS]){ 
-      if chunk = @chunks_by_id[$~[1]]
-        chunk.unmask_text 
+    gsub!(MASK_RE[ACTIVE_CHUNKS]) do 
+      chunk = @chunks_by_id[$~[1].to_i]
+      if chunk.nil? 
         # if we match a chunkmask that existed in the original content string
         # just keep it as it is
-      else 
         $~[0]
-      end}
+      else 
+        chunk.unmask_text 
+      end
+    end
     self
   end
 
@@ -198,9 +197,5 @@ class WikiContent < String
     @revision.page.name
   end
 
-  def page_id
-    @revision.page.id
-  end
-
 end