svnmucc: 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/svnmucc - from package: subversion

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