JMAIL发送邮件时注意的问题

最近使用jmail发送邮件，写了下面一段代码:

String recipients = "[e-mail];[e-mail]";

String[] emails = recipients.split(XmlPAY.SEMICOLON);
  for (String email:emails){
   msg.addRecipient(Message.RecipientType.TO, new InternetAddress(email));

     Transport.send(msg);
  _log.debug("收件人：%s,邮件内容:%s", recipients, message);
}

结果是：[e-mail]邮件收到两封邮件，收件人分别是：1) [e-mail]. 2) [e-mail];[e-mail]

修改代码如下：

String[] emails = recipients.split(XmlPAY.SEMICOLON);
for (String email:emails){
  msg.addRecipient(Message.RecipientType.TO, new InternetAddress(email));
}
Transport.send(msg);
_log.debug("收件人：%s,邮件内容:%s", recipients, message);

  结果正常，具体原因待分析@_@