otr_remac: 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 CentOS possible default full paths are:

/usr/bin/otr_remac - from package: libotr

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/otr_remac - from package: libotr5-bin

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

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