Change path.

app.rb

@@ -144,16 +144,16 @@
   end
 end
 
-post '/entry/:id/comment' do
-  @entry = Entry.get(params[:id])
+post '/comment' do
+  @entry = Entry.get(params[:entry_id])
   @entry.comments.build(
     :name => params[:name],
     :email => params[:email],
     :url => params[:url],
     :body => params[:body]
   )
   @entry.save
-  redirect "/entry/#{params[:id]}"
+  redirect "/entry/#{params[:entry_id]}"
 end
 
 get '/login' do

themes/default/entry/comments.haml

@@ -11,7 +11,8 @@
         = h(comment.body).gsub("\n", "<br />\n")
 
   #comment_form
-    %form{:action=>"/entry/#{entry.id}/comment", :method=>'post'}
+    %form{:action=>"/comment", :method=>'post'}
+      %input{:type=>'hidden', :name=>'entry_id', :value=>entry.id}
       %table
         %tr
           %th