How to set up an eclipse update site and force one optional package?

I developed several plug-ins for eclipse that are bundled in one update site. Until no开发者_JS百科w. Now I have added an extension point to one of the plug-ins and implemented two plug-ins that can hook up to that extension point. I want to set up the update site such that a user is forced to install my package with one and only one of the extension plug-ins. Can I do that ?

Thank you !

A simplest way to create a feature to contains both the plug-in provided the extension point and the plug-in implemented the extension. Then export the feature to a repository.