cpan-listchanges: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/cpan-listchanges - from package: cpan-listchanges

You may install the required package with command apt-get install {package}
Error in other languages:
cpan-listchanges: bevel nie gevind nie
cpan-listchanges: comandă negăsită
cpan-listchanges: comando não encontrado
cpan-listchanges: commande introuvable
cpan-listchanges: command not found
cpan-listchanges: käsku ei ole
cpan-listchanges: không tìm thấy lệnh
cpan-listchanges: komanda nerasta
cpan-listchanges: Kommando nicht gefunden.
cpan-listchanges: kommandot finns inte
cpan-listchanges: komut yok
cpan-listchanges: nie znaleziono polecenia
cpan-listchanges: níor aimsíodh an t-ordú
cpan-listchanges: no se encontró la orden
cpan-listchanges: no s'ha trobat l'ordre
cpan-listchanges: opdracht niet gevonden
cpan-listchanges: parancs nem található
cpan-listchanges: perintah tidak ditemukan
cpan-listchanges: príkaz nenájdený
cpan-listchanges: příkaz nenalezen
cpan-listchanges: команда не найдена
cpan-listchanges: командата не е открита
cpan-listchanges: 命令找不到
cpan-listchanges: コマンドが見つかりません