Plugin Error

Errors in plugins? Retry to Update or Configure.

NoMethodError

undefined method `keys' for nil:NilClass

(plugin/blog-category.rb):135:in `blog_category_entry'
(TDiary::Plugin#eval_src):24:in `eval_src'
/home/tokoi/public_html/lib/tdiary/plugin.rb:95:in `eval'
/home/tokoi/public_html/lib/tdiary/plugin.rb:95:in `eval_src'
/home/tokoi/public_html/lib/tdiary/base.rb:65:in `do_eval_rhtml'
/home/tokoi/public_html/lib/tdiary/base.rb:29:in `eval_rhtml'
/home/tokoi/public_html/lib/tdiary/dispatcher/index_main.rb:37:in `run'
/home/tokoi/public_html/lib/tdiary/dispatcher/index_main.rb:5:in `run'
/home/tokoi/public_html/lib/tdiary/dispatcher.rb:25:in `dispatch_cgi'
index.rb:32:in `<main>'