Great book! but... ermmmm... license keys management?

[Guest]

I really enjoyed reading the book and together with the Official Eclipse 3.0 FAQ, it's a real pleasure to develop plug-ins for Eclipse.

However, it would be nice to have a chapter about how to effectively license a plug-in for Eclipse. Do you have any interesting resources about License Key Management for Eclipse Plug-ins? I would like to implement a system allowing a per-plugin Licensing. What would be the better way to do this? In the Plug-in? as a feature?

???

Thanks for any suggestion!