Well, "setenv RUBYLIB /scripts" was the right solution. I don't quite
understand what was going on; RUBYLIB was set (as verified by typing
"setenv"), but Ruby couldn't find the scripts until I restarted the
computer. Then it seemed to work fine.

But now I'm having another weird problem where accessing the PATH
environment variable is causing Ruby not find scripts. For example:
     /scripts/script1.rb:
          #!/usr/bin/ruby
          print `script3.rb`

     /scripts/script2.rb:
          #!/usr/bin/ruby
          ENV["PATH"].split(/:/).each { |i|
               #do nothing
          }
          print `script3.rb`

     /scripts/script3.rb:
          #!/usr/bin/ruby
          print "Testing...\n"

     Command Prompt:
          [scripts]# cd /testing
          [testing]# script1.rb
          Testing....
          [testing]# script2.rb
          /testing/script2:4: command not found: script3

Any access to ENV["PATH"] seems to cause the problem, for example:
print ENV["PATH"]
tmp = ENV["PATH"]
ENV["PATH"].chomp!

Any ideas on this one?