Ok for anyone interested here are 2 examples of the changes they made, to ril and itelephony. I got this by decompiling the framework.jat file using apktool then using winmerge (with a filter to ignore ".line" in order to reduce the changes). Once winmerge identified the files that were different by comparing the smali code I used dex2jar to decompile the frameworks to java, then I used jd-gui to open the output from that which shows "proper" java. Since jd-gui crashes when saving all files I manually copied the code from the aosp and zte files to text files and then finally used winmerge to compare the java. There are quite a few changes and I'm not sure what the best way to progress is. Note that this is 2 out of 420 files which have changed, but most of those wont be what prevents ril from working for us.
Note I only used apktool because jd-gui errors when saving all files, if that worked ok it would be a lot easier.
I think that realistically the best way of moving forward would be to debug the framework from aosp and zte in order to compare where the different behaviour occurs that causes the problems we have, then identify what may be causing that but it's a lot of work.
Edited by rjm2k, 12 January 2011 - 09:54 PM.