funmerge: 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/funmerge - from package: funtools

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

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