I started getting login popups for another forum on the Solidarity icon (which was showing up as a broken image), so I killed the smiley so that the popups would stop.
(It turns out the smiley was never copied to our server repository, we were hitting this other site for it every time someone used it. So when the other site was down, we'd get broken links and these popups.)
At the moment, you'll likely just see the code itself appearing in the posts that were using it.
If anyone can find another copy of that smiley, I'll upload it to our server and reinstate it. I haven't yet been able to find another copy.