Howto: Install the latest HTC Magic/Sapphire Cupcake Firmware on your android G1!

It no longer is a Dream to be able to run cupcake on your Android G1, thanks to Haykuro an XDA developer member who is active hacking away on the HTC Sapphire firmware and bringing it directly to us Android G1 users, he has been working on it daily while going to school and working a full time job.  Just like the hackers obtained root access on the G1 before it was released, Haykuro has hacked the HTC Firmware mod 4.5 to be fully functional on the Android G1 before the HTC Saffire has been released! 

First of all I need to explain the differences between version 4.5 and version 4.9, people automatically think that the latest version number is the latest firmware, this is not the case with this firmware:

Versions 4.0 and 4.9 are HTC's Build based on the latest Google Android Code

Version 4.9 is highly unstable and does not support all market apps, and when placing/recieving calls your phone crashes after the call, and when a person answers the phone vibrates, I also noticed random reboots and other problems. 

Version 4.5 is based on the latest Google Android code - This is the most stable, it is as stable as JesusFreke's Latest build and I have not had any problems.

Here is the current status of the HTC Magic mod'd firmware:

1. Apps to SD Support added to 4.5 build and 4.9 build.
2. Root/Superuser Access available on all Builds.
3. Camera/Video Recording is working but has a few cosmetic bugs.(blue/red colors are enhanced, can be fixed with photoshop or Gimp) (will be fixed soon)
   
4. Battery life has improved using Android 1.5 with the new Sapphire radio update (Radio version 2.22.19.23)
5. The Android Chrome Browser has been tweaked for a noticably faster experience.
6. Gmail app has nice cosmetic changes with ability to select multiple messages to archive/apply labels and has improved performance
7. MyFaves is not included due to possible copyright issues?
   
8. Wifi and Full A2DP Bluetooth is working on all builds.
9. Live Folders/Contacts on the Home Screen
10. Contact manager is streamlined and has more features
11. Nice Transition Effects(reminds me of compiz)
12. Chat off the Record with Gtalk
13. User dictionary added to shorten the time typing.
14. Autocomplete in most apps.
15. You can either use the device keyboard or software keyboard.

Stable Google Android Version 4.5 cupcake Build Specific Changes from HTC's Build

1. Faster Browser than HTC Build
2. All Google apps work accept IM(the stock im app sucks anyways, I use apps found in the market)
3. Gtalk app works
4. Autorotate all apps and homescreen

Unstable HTC Version 4.9 Specific Features & Changes from Google's Build

1. Native Exchange 2003/2007 included in the HTC builds (ie 4.0 and 4.9)
2. Has issues with Google apps. (No Maps)
   
3. Not able to run all applications in the market(I wasnt able to use Google Voice by Evan Charlton)
4. The popup keyboard is HTC Styled(I dont care for it much)
5. Camera/Camcorder has Zoom

Howto Install:
Warnings...
Make sure your phone is fully charged, while flashing, do not have the urge to press any keys or interrupt the process by pulling the battery or you risk bricking your device.  Patience is a virtue.
You will need to wipe your phone, so be sure to grab the astro filemanager app in the market and press menu, application manager and backup all your apps to sd.

1. First you Need root access and you need to have JF's Firmware installed, see here for updated instructions
2. Once your confident in having root access you are all set to install the HTC Magic mod'd firmware
3. Go Here and download the latest firmware mod for your G1 (as of this post 4.5 is the most stable for daily usage, 4.9 is risky and very buggy)
4. You may want to check the  md5sum/sha1sum of the file you downloaded, it shouldnt be necessary since the zip's are signed, but it would save you a reboot and redownload if you did.
5. Copy the zip to the sdcard and rename it to update.zip
   
6. Power Down your device by holding in Power(red), then shut off.
   
7. Press Power(Red) and Home(Little House) at the same time, until you see scrolling text and JF's recovery bootscreen.
8. Wipe the phone to factory defaults, by pressing ALT-W (make sure all data is backed up before this step :)
9. Now apply the update.zip file by pressing ALT-S and waiting... Give it 10-20 minutes to do its thing, it will reboot a couple times, whatever you do, do nothing until you see the android welcome screen.
10. Ok everything should have flashed correctly, if not and you cant turn on your device, call t-mobile and tell them your phone didnt startup after the latest ota update and get it replaced. 
11. Hundreds of people have done this correctly, the people that didnt pulled there battery early and didnt read, ask around, research.

Enjoy Your new firmware and be sure to follow Haykuro on Twitter for development updates.

Helpful Links & Additional info
Haykuro on Twitter for development updates.
Haykuro's blog for updates, recent builds
JesusFreke's Blog for updates on his firmware
HTC Sapphire/Vodofone Magic G1 Port Xda Dream Developers thread