The code must be unaltered.
I say "same subject" merely to prevent people from thinking they can just send a random e-mail to the server and expect it to be processed.
It actually ignores everything but the code. Also, if you put other ~ characters into the subject, the server will also be unable to process the turn. Hence... leaving it unaltered (with the usual RE or SV or whatever prefix) is the safest way of telling people to use it.
I have one user who uses AOL, which truncates the subject after about 60 characters, in a game with more than 60 chars in the name (one of the tournaments), so he has to edit the subject so the code is seen.
Cheers,
Admiral
------------------
Space Empires IV Play by Web