none said:

zombie84 in avsforum wrote: The SE, unfortunately, shares the same copyright, because they chose not to file an additional copyright but instead filed it under the original one.

I don't think this is the case. Here are the LoC SE records:

http://originaltrilogy.com/forum/topic.cfm/Save-Star-Wars-Dot-Com/post/461093/#TopicPost461093

Here are the Special Edition Library of Congress records:

1997 - Star Wars A New Hope Special Edition
http://lccn.loc.gov/97510343

Acquisition Source:    Received: 4-1-1997; viewing print; copyright deposit--RNR; Copyright Collection.

1997 - Empire Strikes Back Special Edition
http://lccn.loc.gov/98502262

Acquisition Source:    Received: 3/17/97; ref print; copyright deposit--RNR; Copyright Collection.

1997 - Return of the Jedi Special Edition
http://lccn.loc.gov/2006642053

Acquisition Source:    Received: 5/23/1997; viewing print; copyright deposit--RNR; Copyright Collection.

and in those records is the statement:

Notes Copyright: Lucasfilm, Ltd. NM: new visual effects, sound and new footage throughout. DCR 1997; PUB 11Feb97; REG 18Feb97; PA784-125.
Summary taken from Baseline document.
Sources used: copyright data sheet; copyright data base; Baseline data base.

Not sure what NM means. New Medium, maybe. So these record shows that it's a new copyright claim, but built off a previously filed one.

When you see the films, the copyright is 1977. It's 1977 in the onscreen credits, the box, the poster and all other official references, even ones from FOX. So, the new filing was merged into the existing one it seems. Whether it was a separate filing or whatever, it still shares the same copyright foundation of the 1977 original.