@Gary: The link I provided points to a column by William Safire. If I understand him correctly the second meaning you listed is actually fairly new, and by Safire's standards, constitutes incorrect usage or is at least stylistically questionable. One can certainly find a lot of news stories published over the past 10 years or so that use phrases like "the embattled governor/president/CEO/etc".
I guess here is an instance of the case that incorrect usage of a word gets picked up by numerous other writers, becomes commonplace, and finally warrants a new in the dictionary.
The first meaning you listed goes back all the way to the 14th century according to Chambers Dictionary of Etymology, BTW.
Apparently, there is also a special meaning of "embattled" in heraldry:http://www.farreaches.org/cgi-bin/glossary.cg...
"embattled": adj. (of an edge) drawn so as to resemble the battlements of a castle or a square wave.
I am too lazy to pull the appropriate volume of the OED2 right now, but I would bet dollars to donuts that "embattled" in the sense of "beset with attackers, criticism, or controversy" isn't listed yet.