Version:           4.3.0 (using KDE 4.3.0)
OS:                Linux
Installed from:    Gentoo Packages

I opened a directory in dolphin, then clicked on an image.  Accidentally, three gwenviews came up (clicked too many times), so I closed all but one.  After I was done perusing the images, I closed all the gwenviews and dolphin.  At that point, I noticed that a task was still showing up in the task bar with nothing on it other than the gwenview icon.  "pgrep gwenview" shows no such process running.

I've seen bug reports saying that this would cause plasma to crash, which would be annoying in one sense, but at least that task would go away.  Oddly, plasma, which has crashed earlier in this session and restarted, has not crashed again over this.  I can attach a screen shot of the task.