dtomcat6: 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 CentOS possible default full paths are:

/usr/sbin/dtomcat6 - from package: tomcat6

You may install the required package with command yum install {package}
Error in other languages:
dtomcat6: bevel nie gevind nie
dtomcat6: comandă negăsită
dtomcat6: comando não encontrado
dtomcat6: commande introuvable
dtomcat6: command not found
dtomcat6: käsku ei ole
dtomcat6: không tìm thấy lệnh
dtomcat6: komanda nerasta
dtomcat6: Kommando nicht gefunden.
dtomcat6: kommandot finns inte
dtomcat6: komut yok
dtomcat6: nie znaleziono polecenia
dtomcat6: níor aimsíodh an t-ordú
dtomcat6: no se encontró la orden
dtomcat6: no s'ha trobat l'ordre
dtomcat6: opdracht niet gevonden
dtomcat6: parancs nem található
dtomcat6: perintah tidak ditemukan
dtomcat6: príkaz nenájdený
dtomcat6: příkaz nenalezen
dtomcat6: команда не найдена
dtomcat6: командата не е открита
dtomcat6: 命令找不到
dtomcat6: コマンドが見つかりません