wget http://search.cpan.org/CPAN/authors/id/A/AW/AWESTHOLM/Net-SMTP-TLS-0.12.tar.gz -P /opt/
cd /opt/
tar -zxvf Net-SMTP-TLS-0.12.tar.gz
cd Net-SMTP-TLS-0.12
perl Makefile.PL
make
make test
make install

cd /opt
wget https://cpan.metacpan.org/authors/id/T/TO/TOMO/src/Net-SMTPS-0.09.tar.gz
tar -zxvf Net-SMTPS-0.09.tar.gz
cd Net-SMTPS-0.09
perl Makefile.PL
make
make test
make install

wget http://search.cpan.org/CPAN/authors/id/R/RJ/RJBS/Email-Send-2.201.tar.gz -P /opt/
tar -zxvf Email-Send-2.201.tar.gz
cd Email-Send-2.201
perl Makefile.PL
make
make test
make install

cd /opt
wget http://search.cpan.org/CPAN/authors/id/R/RJ/RJBS/Email-Simple-2.214.tar.gz
tar -zxvf Email-Simple-2.214.tar.gz
cd Email-Simple-2.214
perl Makefile.PL
make
make test
make install

cd /opt
wget http://search.cpan.org/CPAN/authors/id/R/RJ/RJBS/Return-Value-1.666005.tar.gz
tar -zxvf Return-Value-1.666005.tar.gz
cd Return-Value-1.666005
perl Makefile.PL
make
make test
make install

或者cpan方式安装：
yum install perl-CPAN
perl -MCPAN -e shell
cpan[1]> reload cpan
cpan[1]> d /smtp/
cpan[1]> install Net::SMTPS

perl -MNet::SMTP -e “print\”module installed\n\””
perl -MNet::SMTP::SSL -e “print\”module installed\n\””
perl -MNet::SMTPS -e “print\”module installed\n\””
perl -MNet::SMTP::TLS -e “print\”module installed\n\””
perl -MAuthen::SASL -e “print\”module installed\n\””