CDBS & Multiple source directories in a single source

[Jonathan Lassoff <jof@thejof.com>]

I'm looking at packaging a library that has a main source tree as well
as a couple of smaller libraries inside of a "contrib" directory. It's
mostly GNU autotools based, so I decided to use CDBS.

Currently, the smaller libraries don't get built or installed from the
top-level makefile, so I'd like to add them as separate binary
packages, but sharing a single source tree.

Is there a nice way to hook into CDBS or some debhelper scripts to go
into another directory and build another package after building the
top-level one?

Cheers,
Jonathan