gs.pvm: 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/gs.pvm - from package: pvm-examples

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