I have this shell function (zsh, but it should work for most Korn-ish shells):

pmver () {
  perl -le "eval { require ${1} }; if( \$@ =~ /locate (\S+)\.pm/ ) { p
+rint qq{${1} not installed}; exit 1; } print qq{${1}: },\$${1}::VERSI
+ON||q{undefined}"
}
[download]

It's used like this:

$ pmver CGI
CGI: 3.05     
$
[download]