Roger that, thanks!
On another note it looks like my original premise is inaccurate. Unfortunately I have found 2 BATFE documents that directly and indirectly seem to state that importing shotguns with magazine capacities of more than 5 rounds is indeed still prohibited even after the September 2004 Assalut Weapons Ban expiration. The bizarre thing is that it does not seem to differentiate between semi-auto and pump!? Could this possibly be something American gun manufactures lobbied for to protect their own business interests, and corner the tactical shotgun market? Sounds crazy.
What I want to find is some sort of official detailed listing of importation regulations.