Can't add plugins using `phonegap plugin add XXX`

Can't add plugins using `phonegap plugin add XXX`

I've installed phonegap version 3 using npm install -g phonegap and now i
want to install plugins for the andriod app
I installed node.js
C:\var\www\sexdiaries.co.uk\app>node -v
v0.10.17
Then Phonegapy
phonegap plugin add
https://git-wip-us.apache.org/repos/asf/cordova-plugin-splashscreen.git
But this gives this error:
[error] 'plugin' is not a node
C:\Users\Hutber\AppData\Roaming\npm\node_modules\phonegap\bin\phonegap.js
command.
See 'node
C:\Users\Hutber\AppData\Roaming\npm\node_modules\phonegap\bin\phonegap.js
help'