503 Service Unavailable (OpenURI::HTTPError)

/usr/local/lib/ruby/1.8/open-uri.rb:277:in `open_http'
./tdiary.rb:92:in `join'
./tdiary.rb:92:in `safe'
./tdiary.rb:688:in `eval_src'
./tdiary.rb:1024:in `do_eval_rhtml'
./tdiary/lib/xtd.rb:210:in `do_eval_rhtml'
./tdiary.rb:966:in `eval_rhtml'
index.rb:113