*fix a database synchronization problem on mail transfer.
修正一个数据库多连接不同步可能导致的邮件传递问题.
*improve a simple HTML source .eml file open problem for Outlook express.
改进Outlook express打开下载的简单HTML源文件乱码问题.
*send a notify mail to admin@ when new account created.
当新帐号被创建时向admin@帐号发送一封通知邮件.
*add once import limit (<=20000) when upgrade from AAMail 4.2X to avoid not enough memeory.
限制从4.2X升级时一次最多导入20000封邮件(可以多次导入)以避免内存不够:[Setup] UpgradeImportMaxOnce=20000。