hpmkdir: 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/bin/hpmkdir - from package: hfsplus

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

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