cvs-mailcommit: 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/cvs-mailcommit - from package: cvs-mailcommit

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

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