I just had a quick look at the recall notice
http://www.cpsc.gov/cpscpub/prerel/prhtml09/09214.html
and if there is an "R" on the hinge face, then it has been "repaired" and is excluded from recall. So that means if yours is from that particular time, it could be one for recall. But since it is a design fault, replacing it with the same thing but repaired, probably means they Loctited the heck out of all the screws, something you could as well.
So you can't actually tell by looking at it if it is a recalled unit?
It's also probably not a design fault, because only some Radius's were recalled and not all, and since we know Dahon sent out actual replacement units (i.e. complete handle post assemblies), they likely did not simply Loctite as you suggest, and it points to the idea it was a metallurgical issue, perhaps improperly spec'd heat treatment. Were it just a bolt issue, even an improperly forged locking plate, you'd think they'd have just sent out those few bits for quick, easy, and less expensive repairs.
Of course, though, I don't know what the true cause of the recall was, and am just speculating. Dahon Global's (i.e. Josh Hon's) statements seem to suggest fault with Dahon China quality control, but looking at those statements in light of the acrimonious company split and Tern development could just as easily be indicative of familial hostility.
I find the Dahon/Tern story fascinating, and am interested to learn more about how this rift emerged.
EDIT: I should add that I appreciate your patience, Jur, as I grill you here; I know you've been paying attention to this issue much longer than I have, and that you're a trove of information!