Good find! I totally agree with you that this must be addressed soon. At least before full release. Maybe there's a way to put invisible walls as borders on the actual map border? I have no idea how the ARMA2 engine works but at least it's something. Auto banning for exploiting in a early/mid alpha is somewhat strange in my opinion. The mod is labeled alpha for a good reason; testing. But that's all up to the dev's and admins :)