dh_gtkmodules: 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/bin/dh_gtkmodules - from package: libgtk2.0-dev

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

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