ascii85: 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/ascii85 - from package: rubygem-Ascii85
/usr/lib/ruby/gems/1.8/gems/Ascii85-1.0.1/bin/ascii85 - from package: rubygem-Ascii85

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

On Debian possible default full paths are:

/usr/bin/ascii85 - from package: ruby-ascii85

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

Error in other languages:
ascii85: bevel nie gevind nie
ascii85: comandă negăsită
ascii85: comando não encontrado
ascii85: commande introuvable
ascii85: command not found
ascii85: käsku ei ole
ascii85: không tìm thấy lệnh
ascii85: komanda nerasta
ascii85: Kommando nicht gefunden.
ascii85: kommandot finns inte
ascii85: komut yok
ascii85: nie znaleziono polecenia
ascii85: níor aimsíodh an t-ordú
ascii85: no se encontró la orden
ascii85: no s'ha trobat l'ordre
ascii85: opdracht niet gevonden
ascii85: parancs nem található
ascii85: perintah tidak ditemukan
ascii85: príkaz nenájdený
ascii85: příkaz nenalezen
ascii85: команда не найдена
ascii85: командата не е открита
ascii85: 命令找不到
ascii85: コマンドが見つかりません