Some work has been done on this during GSoC 2008 by Kurt Maier (kfx).

Bobg says... (from 2008.08.07 email)

  As some of you know, Kurt (kfx on IRC) has been working on an algorithm for 
  fossology to use in a dependency agent.  Here are some of the questions that 
  such an agent (by looking at autoconf files, and source) should be able to answer:
  
  1. what packages use library/file/package X 2. what dependencies (library/file/
  package) are not included in package Y 3. what library/file/packages are included 
  in package Z 4. what library/file/packages are included in package Z but unused.
  
  This information could also be combined with existing license information.  For 
  example, it allows one to see that a package has incompatible licenses, but each 
  file tree (the file and all it's dependencies) does not.

See original RFC thread here:  http://fossology.org/pipermail/fossology/2008-August/000431.html