> I'm running into a problem installing rails using gem.  How do I fix 
> this?

You don't have RDoc installed. Debian has chopped off Ruby into tiny 
packages. Have a look at http://www.rubyonrails.org/show/RailsOnDebian 
for help.
--
David Heinemeier Hansson,
http://www.basecamphq.com/   -- Web-based Project Management
http://www.rubyonrails.org/  -- Web-application framework for Ruby
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http://www.loudthinking.com/ -- Broadcasting Brain