3d bin packing

This is something thats been giving me headaches trying to figure out.

Say you have a set of any number of boxes of any size and a second set of boxes of any size.

How could you find the smallest box from set two that you could fit all the boxes from set one into? This is for a shipping application.

Can any of you figure this out? I've had trouble sleeping trying to figure it out. Google has only taught me that this type of problem is called three dimensional bin packing. I havn't been able to find anything useful. Thanks for any help or suggestions.

PHP code a big plus.

Some random items that might help...

An algorithm in C:
http://www.diku.dk/~pisinger/3dbpp.c

Code and research papers:
http://www.or.deis.unibo.it/researc...des/TSpack.html

Paper discussing the problem with code examples:
http://archive.cs.uu.nl/pub/RUU/CS/...996/1996-39.pdf

US Air Force paper with flow chart, diagrams and an algorithm:
http://www.au.af.mil/au/database/pr...-ens-01m-02.pdf

It's a couple years too late but this might help others who are trying to tackle the 3D bin packing problem. Instead of re-inventing the wheel, perhaps you could use the free 3D Bin Packing service provided at SolvingMaze.com through their API.