Fire Particles on grass

I joined the server and flew around a little. I went to see the house that my friend had made and when I entered, what I saw was what is in the video. The other guy in the video, askaskj2, replaced the flooring after the video was shot, and the effect could still be seen. Re-logging got rid of the error. I haven't experienced it again, but then I haven't played more than a few hours of 1.4 yet.

http://youtu.be/smUnept6XYw