Problems installing exception_notification plugin


I am, trying to install the exception_notification plugin for rails.
I am using rails 2.3, and Windows 7 (64 bit)

The Rails 3 version is here:
I can install it using git-bash thus:
ruby script/install plugin
This works fine.

However, I am trying to install the version of the plugin which is
compatible with Rails 2.3
It is here:
However, when I try the following in git-bash:
ruby script/install plugin
I get the error:
fatal: remote error: rails/exception_notification/tree/2-3-stable/ is
not a valid repository name.

Any ideas how I can install the 2.3 branch of this plugin?
Thanks in advance.