:fr Leslie Viljoen [mailto:leslieviljoen / gmail.com] 
# c:\Program Files\Microsoft Visual Studio 8\VC>fri -f plain Test::Unit
# (druby://127.0.0.1:1310) 
# c:/ruby/lib/ruby/1.8/rdoc/ri/ri_descriptions.rb:99:in `
# concat': can't convert nil into Array (TypeError)
#         from (druby://127.0.0.1:1310) 

fyi, it does not fail here:

C:\Documents and Settings\botp>fri -f plain Test::Unit
------------------------------------------------------ Class: Test::Unit

TEST::UNIT - RUBY UNIT TESTING FRAMEWORK
========================================

Introduction
------------
     Unit testing is making waves all over the place, largely due to the
     fact that it is a core practice of XP. While XP is great, unit
     testing has been around for a long time and has always been a good
     idea. One of the keys to good unit testing, though, is not just
     writing tests, but having tests. What's the difference? Well, if
     you just _write_ a test and throw it away, you have no guarantee
     that something won't change later which breaks your code. If, on
     the other hand, you _have_ tests (obviously you have to write them
     first), and run them as often as possible, you slowly build up a
     wall of things that cannot break without you immediately knowing

[snip long text]

C:\Documents and Settings\botp>ver
Microsoft Windows XP [Version 5.1.2600]

C:\Documents and Settings\botp>ruby -v
ruby 1.8.5 (2006-08-25) [i386-mswin32]

kind regards -botp