Howto install Sophos 5 silent?

Hi there,

I've tried to find a way to install sophos 5 silently, but hadn't any success.

Allthough I don't like AutoIT, I wrote the following script

AutoItSetOption("TrayIconHide", 0)
AutoItSetOption("WinTitleMatchMode", 4)
BlockInput(1)

;open Setup
Run("sophos_setup.exe")

;Welcome Screen
WinWaitActive("Sophos Anti-Virus Installations-Wizard")
Send("{ENTER}")

;Choose folder
WinWaitActive("Sophos Anti-Virus Installations-Wizard")
Send("{ENTER}")

;Choose data for automatic updates ( enter data later )
WinWaitActive("Sophos Anti-Virus Installations-Wizard")
Send("!i")
Send("{ENTER}")

;Start installation
WinWaitActive("Sophos Anti-Virus Installations-Wizard")
Send("{ENTER}")

;Finish installation
WinWaitActive("Sophos Anti-Virus Installations-Wizard")
Send("{ENTER}")

Problem is, that the last ENTER to finish the installation isn't send.

I would be glad to get any help.