Perl Authen::Captcha

Установка FreeBSD

cd /usr/ports/security/p5-Authen-Captcha/ && make  && make install clean
cd /usr/ports/devel/p5-String-Random/ && make  && make install clean

Установка Ubuntu, Debian

apt-get install  libauthen-captcha-perl

Установка с CPAN

perl -MCPAN -e shell 
install Authen::Captcha

Установка CentOS

yum install perl-Authen-Captcha