rmsgmerge: 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/rmsgmerge - from package: ruby-gettext

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

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