bee propolis

Anyone have the straight dope on bee propolis? I have some co-workers who swear it knocks their colds down to 2-day annoyances when others around them suffer week long bouts of nastiness.

I don’t believe a word of it, but can’t find any data to support or deny their claims. And the argument that “bees don’t get colds” just doesn’t seem to work for those of us with brains.

Any data out there to show this is yet another homeopathic pipe dream? Or heck, I’ll take data saying it’s the real deal, too, if there’s real science behind the claim. Anyone hear of this stuff?