Adding plugins for eclipse

[David Goodenough <david.goodenough@btconnect.com>]

I am running debian format eclipse on an unstable box, and I want to add a
plugin (the Swt-Designer plugin as it happens).

I think I understand from the docs and bits I have found on the web that
I should put the plugin in ~/.eclipse/eclipse/plugins, but I am not quite
sure.  I tried that and it did not seem to work.

Do I have to add anything to ~/.eclipse/user.links?  

Where do I put the plugins if I want them available to all users rather
than just me?

Thanks in advance

David