sf-add-skill: 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/sf-add-skill - from package: gforge-db-postgresql

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

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