nexuiz-dedicated: 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/nexuiz-dedicated - from package: darkplaces-server

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

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