rmiregistry: 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/lib/jvm/java-1.5.0-gcj-4.8-amd64/bin/rmiregistry - from package: gcj-4.8-jre-headless
/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64/jre/bin/rmiregistry - from package: gcj-4.8-jre-headless
/usr/lib/jvm/java-1.5.0-gcj-4.9-amd64/bin/rmiregistry - from package: gcj-4.9-jre-headless
/usr/lib/jvm/java-1.5.0-gcj-4.9-amd64/jre/bin/rmiregistry - from package: gcj-4.9-jre-headless
/usr/lib/debug/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/rmiregistry - from package: openjdk-7-dbg
/usr/lib/jvm/java-7-openjdk-amd64/bin/rmiregistry - from package: openjdk-7-jre-headless
/usr/lib/jvm/java-7-openjdk-amd64/jre/bin/rmiregistry - from package: openjdk-7-jre-headless

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

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