old-db-upgrade.pl: command not found

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/share/gforge/bin/old-db-upgrade.pl - from package: gforge-db-postgresql

You may install the required package with command apt-get install {package}

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