elq: 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/elq - from package: qmail
/var/lib/qmail/bin/elq - from package: qmail

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