wmlxgettext: 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/wmlxgettext - from package: wesnoth-tools

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

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