sb2-mkinitramfs: 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/sb2-mkinitramfs - from package: scratchbox2

You may install the required package with command apt-get install {package}
Error in other languages:
sb2-mkinitramfs: bevel nie gevind nie
sb2-mkinitramfs: comandă negăsită
sb2-mkinitramfs: comando não encontrado
sb2-mkinitramfs: commande introuvable
sb2-mkinitramfs: command not found
sb2-mkinitramfs: käsku ei ole
sb2-mkinitramfs: không tìm thấy lệnh
sb2-mkinitramfs: komanda nerasta
sb2-mkinitramfs: Kommando nicht gefunden.
sb2-mkinitramfs: kommandot finns inte
sb2-mkinitramfs: komut yok
sb2-mkinitramfs: nie znaleziono polecenia
sb2-mkinitramfs: níor aimsíodh an t-ordú
sb2-mkinitramfs: no se encontró la orden
sb2-mkinitramfs: no s'ha trobat l'ordre
sb2-mkinitramfs: opdracht niet gevonden
sb2-mkinitramfs: parancs nem található
sb2-mkinitramfs: perintah tidak ditemukan
sb2-mkinitramfs: príkaz nenájdený
sb2-mkinitramfs: příkaz nenalezen
sb2-mkinitramfs: команда не найдена
sb2-mkinitramfs: командата не е открита
sb2-mkinitramfs: 命令找不到
sb2-mkinitramfs: コマンドが見つかりません