sudo apt-get install sendEmail libnet-ssleay-perl libio-socket-ssl-perl or download from “http://caspian.dotconf.net/menu/Software/SendEmail/sendEmail-v1.56.tar.gz“ sendEmail -f “unotseeme@gmail.com”   -t “unotseeme@qq.com”   -u “hello world”   -m “hello world”   -o tls=yes   -s smtp.gmail.com:587   -xu “unotseeme@gmail.com”   -xp “xxxx” on centos: http://pkgs.repoforge.org/perl-Net-SSLeay/perl-Net-SSLeay-1.36-1.el5.rfx.x86_64.rpm http://packages.sw.be/perl-IO-Socket-SSL/perl-IO-Socket-SSL-1.34-1.el5.rfx.noarch.rpm