how to load a plugin on the run?

Hey all,
I have a multisite app and I want to load certain plugins for each of
them. Is there a way to use a before_filter that would load a given
plugin by looking at the url? If so how?

thanx in advance

Pat

That won't work because there's no real way to unload a plugin for
another app that doesn't use it.

Ok thanx, is there a way then to load them all and ignore some of them
for a given url?

Plugins are loaded when the server starts, and cannot be unloaded or
reloaded dynamically for each request.

I think your best bet will be to find another angle to approach your
problem. It sounds like the different sites your current application
runs have sufficiently-different behaviour that they may need to be
different applications entirely...