I think it would be nice, if the farmworld would get a similar warning for "You placed your claim inside a world that will be reset" like the nether. I noticed it in the regrowth-server that some people build their camps in the farmworld without knowing about this. And when people ask if they are in the farmworld, the only way seem to be, that they give you the coords and someone else runs to this location in the overworld. In case that there "should" be a warning: I tried it, went to the farmworld and put a claim there, but I didn't get any warning. So in that case the script for the warning might be broken on regrowth.
Ah, I see. I didn't put a chest there but used the golden shovel to claim. Guess that doesn't trigger the warning. Good to know and thanks for this hint And also thanks for the "/getpos" command, didn't know about that command till now. Next time I know better when someone asks :]