Enter the perl CPAN shell:
perl -MCPAN -e shell
List installed module versions:
perl -MCPAN -e 'CPAN::Shell->r'
List installed module versions (from inside the shell):
perl -MCPAN -e 'o conf init'
Good tips on using CPAN: http://sial.org/howto/perl/life-with-cpan/
You can reconfigure CPAN completely by using 'o conf init' at the cpan prompt. Or you can configure a single option with o conf followed by the option and the values you want to set. Then use 'o conf commit' to save the changes permenantly. Entering just 'o conf' will show the current settings
Installing through CPAN is dangerous because it doesn't have an uninstall command and modules you install are not registered in a package manager (and therefore can only be removed manually). Use
cpan2rpm to create RPMs from CPAN modules: http://perl.arix.com/cpan2rpm/
# rpm -Uvh ~alan/cpan2rpm-2.028-1.noarch.rpm