Illegal instruction by an empty locale????

 I have just got access to a hand-made PC cluster, and I encounter an interesting problem.

A compute node complains of "illegal instruction", while the architecture is almost the same as that of the head node (Sandybridge, and Haswell). Furthermore, I experienced the problem even with binaries compiled on the compute node. That is totally clueless.

When I login (yeah, it is allowed, luckily) to a compute node, I realize that the terminal says

"-bash: warning: setlocale: LC_CTYPE: cannot change locale (ja_JP.utf8): No such file or directory".

I did the following half in doubt, and the "illegal instruction" disappears!;
"export LC_ALL=en_US.utf8"

I do not know what is really going on, but this is my story.