No doubt the devs are doing magics with their images but probably there are many conservative people who want to stay with their original firmwares.
So here we go:
My phone was runnig RUU_Saga_HTC_Europe_1.28.401.1_Radio_20.28b.30.080 5U_38.03.02.11_M_release out of the box first. It was S-ON. I S-OFFed it using Alpharevx and then I rooted it with Gingerbreak 1.20. Then I decided to update the phone with the stock RUU_Saga_HTC_Europe_1.47.401.4_Radio_20.28I.30.085 AU_3805.06.02.03_M_release_199410_signed and I lost my root but the phone was still showing S-OFF. Rooting with Gingerbreak is not working on 1.47.xxx ROMs. I rooted it using 4EXTRecovery v2.1.0 FINAL and this file from http://unrevoked.com/rootwiki/doku.p.../revolutionary
To install 4EXTRecovery v2.1.0 FINAL on a non rooted phone(thanks to madmaxx82 and .sh4d0w.):
1. Download and unzip on your PC the attached 4EXTRecovery v2.1.0 FINAL.zip file
2.Copy all 5 files to the C:\ directory of your PC.
3.Connect your phone to the PC(debug usb option activated) charge only
4.Run cmd to open console, point to the directory where you copied the files and type: adb reboot bootloader - device will boot into the bootloader
5.Type: fastboot flash recovery recovery.img
After reboot you should have 4EXTRecovery installed available from recovery option on your hboot menu.
6. Copy to the root of your SD Card the file su-220.127.116.11-efgh-signed.zip which you can download from here
7.Go to the 4EXTRecovery > install from sd card and choose su-18.104.22.168-efgh-signed.zip
8.Done. After reboot you should have SUPERUSER installed and your phone is rooted again
To get Ad hoc wifi support:
9.Download and unzip the attached Ad hoc.zip file to your PC.
10. Install from 4EXTRecovery ADHOC.v2.zip file and reboot.
11.Copy and replace wpa_supplicant file to: /system/bin
(you can use file expert apk from the market to do that)
Done. You have an Ad hoc wi-fi support.
YOUR PHONE MUST BE S-OFF BEFORE TO START THIS PROCEDURE!!!
DO IT ON YOUR OWN RISK!
You can have a look here for double check: http://forum.xda-developers.com/show...&postcount=184