500 Internal Server Error

undefined method `<' for nil:NilClass (NoMethodError)

/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/core_ext.rb:79:in `safe'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/config.rb:229:in `load_cgi_conf'
(tdiary.conf):217:in `configure_attrs'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/config.rb:134:in `eval'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/config.rb:134:in `configure_attrs'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/config.rb:12:in `initialize'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/dispatcher/index_main.rb:14:in `new'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/dispatcher/index_main.rb:14:in `initialize'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/dispatcher/index_main.rb:6:in `new'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/dispatcher/index_main.rb:6:in `run'
/virtual/qteamer/public_html/www.qteamer-soft.com/tdiary/dispatcher.rb:21:in `dispatch_cgi'
index.rb:36:in `<main>'