jimbeetle - 8:50 pm on Aug 5, 2010 (gmt 0)
Just by their nature newspaper sites are pretty much considered authorities in their own right and Google crawls them very regularly. So of course Google is going to credit the "authority" where it first sees the article as the originator.
The two-week window in your second post is probably a result of the article dropping down the hierarchy of the newspaper site and staying somewhat higher on the site with which you're working.
Not really sure if there's anything that can be done about this. If the page titles and descriptions are close to the same as the newspaper sites you might consider fiddling these a bit to get around the initial dupe content filter.
Hopefully other folks will have better ideas.