hdate: 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/hdate - from package: hdate

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

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