Common Extensions Directory

I’m using the technique described here:

It’s working fine except now I want to have a /common/protected/extensions directory where I can put extensions that some or all of my apps use but for each app i want to also keep their own extensions directories.

Is there any way to use the ‘ext’ alias for both paths? I assume not but I don’t want to go in and change some calls to extensions to use a common.extensions alias.