After 3+ years, Booda, I dunno if your 441 XLR is still wigglin', but here's some more info:
I've bought two of them used in the last few months - just got the second one today. The first one has quite a bit XLR jiggle. This second one has (had) a little, but it's also missing the logo badge which is right underneath the bass rolloff switch (hmm.. didn't notice that in the ebay pic) - this exposes a fairly large flatheaed screw that is holding the XLR assembly in place. I tighten the screw and, voila, no more jiggle.
It does not appear that the badge came off gracefully - there's a bit of plastic framing (shared with the bass rolloff switch) missing, and what looks like some glue, perhaps from an attempt to re-attach it in its former life.
When I get home, I'm going to look at how do-able it would be to remove-then-reaffix the badge on the other one. If it doesn't look like a good idea, I think I'll just put up with the jiggle. Seeing what I see on this one (I can pull the XLR assembly completely out with the screw removed, and there are two wires running from it to the body), I don't think the jiggle is much more than an annoyance. It *could* be that the screw completes the ground connection with the body, in which case if it loses contact the mic will hum, but that doesn't seem like a big possibility with the badge on, holding the screw in place.