Forum OpenACS Development: Help needed on porting outer joins in static-pages

I am working on porting static pages and I came up against the following query in commentability.xql:

        FIX ME DECODE (USE SQL92 CASE) 
  	select spf.folder_id,
  		decode
(spf.folder_id,:root_folder_id,'[acs_root_dir]/www/',content_item.get_
title(spf.folder_id)||'/') as folder_name,
  		static_page.five_n_spaces(lev) as spaces,
  		static_page_id,
                  substr(filename,instr(filename,'/',-1)+1) as 
filename,
                  decode(p_file.grantee_id,NULL,'not 
commentable','commentable') as file_permission,
  		decode(show_comments_p,'t','comments 
displayed','comments summarized') as display_policy,
                  decode(p_folder.grantee_id,NULL,'children not 
commentable','children commentable') as folder_permission
  from static_pages sp,
     (select folder_id,level as lev from sp_folders
      start with folder_id = :root_folder_id
      connect by parent_id = prior folder_id) spf,
     acs_permissions p_file,
     acs_permissions p_folder
  where spf.folder_id=sp.folder_id(+)
    and p_file.grantee_id(+) = acs.magic_object_id('the_public')
    and p_file.privilege(+) = 'general_comments_create'
    and p_file.object_id(+) = static_page_id
    and p_folder.grantee_id(+) = acs.magic_object_id('the_public')
    and p_folder.privilege(+) = 'general_comments_create'
    and p_folder.object_id(+) = spf.folder_id
   

I added a tree_sortkey column and triggers to sp_folders and ported the connect by and also ported the decodes. The outer joins are making my head spin. Any help is appreciated!