... and I did the first web application using it, now I'm going to create the second.

In this first web application I enhanced the framework's core library with new things and promptly updated framework branch.

I'm using bazaar to keep framework and web application committed. The application was in the beginning, a full branch of framework source tree, now I'm updating framework manually at every change on core files. (copying changed files from web app to framework's branch).

With this second web application that I'm going to create, I need to know about versions (or revisions) which the application is based. If I found a bug in this version I can fix and then sync files with first web application no worrying: functions will be the same to this application.

If I'm going to make changes in core (new behavior, new functions in library or something new in source tree) it must be named as "new version".

What's the best way to do this?

Because I'm using a Distributed Version Control System (bazaar), I'm not dealing with VERSIONS, but revision numbers that change every time.

Please fresh my mind with new ideas.