On Dec 17, 2010, at 18:32, Intransition wrote:

> It occurs in 1.8.7 and 1.9.2.
> 
> $ ri -f html String
> /home/trans/.rvm/gems/ruby-1.9.2-p0/gems/rdoc-2.5.11/lib/rdoc/markup/
> to_html.rb:192:in `accept_rule': undefined method `>' for nil:NilClass
> (NoMethodError)

I see you filed a bug report but no patch.  I will fix it when I have time.