I recently posted on here about how I was going atempt to unlock and jailbreak my G1…and as promised here is the exact steps I took.
YOU ARE DOING THIS AT YOUR OWN RISK!
To do this hack you will need to start the “telnetd” service via terminal emulator which can be downloaded from the Android Market. The only touble is you will most probably need to downgrade your firmware as Google has fixed this loophole with the latest firmware version. If you need to downgrade the firmware please follow these instructions. PLEASE BACKUP ALL DATA OFF YOUR G1 AND MEMORY CARD OR IT WILL BE LOSSED DURING THE FLASHING PROCESS!
Downgrade Firmware
- If you are in the UK you will need to download the RC7 image firmware or if in the US you will need the RC29 these are the downgrade firmwares you will need to install to your G1 before you can gain root access.
- Format your SD card to FAT32
- From the files you have downloaded we now need to extract these and copy DREAMIMG.nbh file onto the root of your memory card, you can do this by connecting your G1 to your USB port of your computer and browsing the removable disk that appears.
- MAKE SURE YOU HAVE BACKED EVERYTHING UP!
- Power Off Device
- When all power is off, hold the Camera button and the Power button at the same time to boot your device into bootloader mode. The screen that appears should show you instructions on how to flash your phone.
- Follow instructions on screen and and press the power button to start the downgrade procedure. Do you do anything to interrupt this process otherwise you could end up with a bricked G1, also make sure you have a full battery!
- Restart your phone when it is finished (I had a little trouble at this point where my phone would not restart so I had to pull the battery but all was well)
Thats the easy bit! Now you need to do the following!
- Download the recovery image file and copy it to your SD card like we did before with the RC7/RC29
- Download the HardSPL and copy the zip to the SD card
- All the files must be on the Root of the SD card, by root this means not in any folders/sub folders on the card.
- Reboot your phone (normal way) and wait for it to come back to the home screen
- When the phone comes back up slide out the keypad and type “telnetd” and you should see the contact list fire up (just ignore this its the telnetd process we need to start up, this will be run in the background so just get rid of the contact list when it appears (after you have typed telnetd)
- Right now you will need to download the Terminal Emulator from the Android Market.
- Once the Emulator is installed you will need to connect to your wireless network
- Fire up the Terminal Emulator and type “ifconfig”
- This will show you the phones internal IP address (write this down unless you have a good memory!)
- Download the Telnet application from the Android Market
- Fire it up once it has installed and if root access is there you should see #
- The following commands will make it easier for you to have root access in the future!
- Type the following into the telnet client
- mount -o rw,remount -t yaffs2 /dev/block/mtdblock3 /system (press return)
- cd sdcard (press return)
- flash_image recovery recovery.img (press return)
- cat recovery.img > /system/recovery.img (press return)
You should now hopefully have root access to your phone!
You now have to apply the HardSPL to your phone which will allow you to use US/UK flash files on the phone, latest android sources and unbrick your phone if it ever happens! Which if you like messing around with technology it most probably will! 
- Power off your phone
- Start up in recovery mode by holding home and pressing power.
- You will now enter recovery mode. You should see an exclamation.
- If you do not see a menu on screen, press Alt-L to show the menu.
- Press Alt-S to apply the update from the SD card.
- After the update is complete, hold Home and press Back to restart.
Now its time to upgrade the firmware to the latest one which is much better, dont worry you will still have root access so all this hard work will not be for nothing!
Android Dev Phone 1
ADP1: (md5: 96b2abd9a1da2852bc33b2052ea51b2a)
http://jf.nyquil.org/v1.31/JFv1.31_ADP1.zip
http://android-dls.com/forum/index.p…rb_v=viewtopic
http://www.gotontheinter.net/content/new-images-jf (at bottom of page)
US RC30
RC30: (md5: 0f2e6a4244410e00028db55b4fbf808c)
http://jf.nyquil.org/v1.31/JFv1.31_RC30.zip
http://android-dls.com/forum/index.p…rb_v=viewtopic
http://www.gotontheinter.net/content/new-images-jf (at bottom of page)
UK RC8
RC8: (md5: e008bbe1d93abd0c2e5e6218f012f20d)
http://jf.nyquil.org/v1.31/JFv1.31_RC8.zip
http://android-dls.com/forum/index.p…rb_v=viewtopic
http://www.gotontheinter.net/content/new-images-jf (at bottom of page)
- Download the image.
- Rename it to update.zip.
- Copy it to your phone’s SD card.
- Turn your phone off.
- Start up in recovery mode by holding Home and pressing Power.
- Press alt-W to wipe your device. (You need to do this, or the device may hang at the flashing Android screen)
- Press alt-S to apply the update.
Magic all is complete Enjoy!
Works! Love it!
Hi, thanks for the detailed walkthru. Can you confirm the procedure will unlock the G1 to any UK network like Voda, O2 etc and that you lose no functionality of the phone. Also, how do you check if the firmware needs downgrading, as mine says “frmware 1,0″
Thanks in advance!
Nope, it let’s you change the firmware – but doesn’t remove the service lock, so it won’t allow you to use it on other networks.
works great – this doesnt count for unlocking to sim unlock but works amazingly!
try out this guide!