Install 3rd part plugins problem

Can anyone tell me whats wrong here.

I am running ruby on rails on windows XP using radrails plugin in
eclipse.

I can install the plugins that show up in the radrails plugin tab like
file_column etc ok. When i try to intall a 3rd part plugin like
cartographer i just get a folder structure containing empty files with
the following in comments like below:

Svn:::::Cartographer.rubyforge.org::Trunk::Vendor::Plugins::Cartographer

I then opened a command window and changed directory to the root of my
application and type: ruby script/plugin install cartographer i get the
following message:
Cartographer plugin not found.

Or if i type in ruby script/plugin install
svn://rubyforge.org//var/svn/cartographer/trunk i get the following
message Cartographer plugin already installed.

Can some one help me out please? It cant be that hard to install a
plugin! Even if i could download the file structure myself and then
move into the vendors folder manually it would help.