*add domain SPF verification.
增加域名SPF验证功能.
*add SMTP/POP3 IP block function when authentication fails times.
SMTP/POP3在密码多次尝试失败以后锁住IP 1分钟.
*add domain SPF verification.
增加域名SPF验证功能.
*add SMTP/POP3 IP block function when authentication fails times.
SMTP/POP3在密码多次尝试失败以后锁住IP 1分钟.