There are three ways you can do a PatchRom build, By 'scratch building' the proper resources by hand via decompiles, by doing an ADB pull on your phones stock rom to obtain target files and by just building if the phone is supported by MIUI which this one is not.
So it really only leaves one option.
Make sure your Linux Build-env is set up correctly
repo init -u git://github.com/MiCode/patchrom.git -b jb
This will pull all the needed Jellybean files from MiCode Repo
the next part is a bit more obnoxious, make sure your phone is connected and make sure ADB is in proper working order..
open a terminal in your main Patchrom folder, and:
adb reboot recovery
Your phone will now begin booting into recovery, let it do it's thing, when recovery has loaded run the following commands in terminal
It will begin dumping everything PatchRom needs from your phone, resulting in a StockRom.zip, you can flash it to make sure everything is in working order or not; it really does not matter
Run the following command
cp ../i9100/makefile .
This will copy the i9100s Makefile over to the working folder, which will need to be modified to suit the phone and the stock-specific APKs, etc.
Once this is done run
And PatchRom will begin to build, being an unsupported phone expect to see errors in your life here & there, If a FullOTA.zip is created in the Out folder of 'razrhd' then you have successfully patched Stock, If there are errors they will need to be resolved before Stock can be built.
If you like MIUI check out my development blog!
-MIUIv5 PatchRom Weekly
Galaxy Exhibit 4g
props to i8150 porters and also LeeBlitz