When posting a comment to a news item, the notice label_comment_added is displayed to the user. I figured that it was inconsistent not to do the same for forum comments, so I created the following patch.

### Eclipse Workspace Patch 1.0
#P Redmine
Index: lang/en.yml
===================================================================
--- lang/en.yml (revision 2344)
+++ lang/en.yml (working copy)
@@ -536,6 +536,7 @@
 label_message_new: New message
 label_message_posted: Message added
 label_reply_plural: Replies
+label_reply_added: Reply added
 label_send_information: Send account information to the user
 label_year: Year
 label_month: Month
Index: app/controllers/messages_controller.rb
===================================================================
--- app/controllers/messages_controller.rb  (revision 2338)
+++ app/controllers/messages_controller.rb  (working copy)
@@ -47,6 +47,7 @@
     end
     if request.post? && @message.save
       attach_files(@message, params[:attachments])
+      flash[:notice] = l(:label_message_posted)
       redirect_to :action => 'show', :id => @message
     end
   end
@@ -60,6 +61,7 @@
     if !@reply.new_record?
       attach_files(@reply, params[:attachments])
     end
+    flash[:notice] = l(:label_reply_added)
     redirect_to :action => 'show', :id => @topic
   end