On Dec 3, 2009, at 03:55 , Wybo Dekker wrote:

> Since moving to ruby-1.9.1-p243, when I try to install the rio gem, I get:
> 
>  $ sudo gem install -r rio
>  Successfully installed rio-0.4.2
>  1 gem installed
>  Installing ri documentation for rio-0.4.2...
>  Updating class cache with 2676 classes...
>  Installing RDoc documentation for rio-0.4.2...
>  ERROR:  While executing gem ... (NameError)
>      uninitialized constant Generators::SM

that's old rdoc. not sure how/why you're hitting that. But `sudo gem install rdoc` and try rio again.