I wonder if there is a way to change the apk or program to make it think your are running ICS so it still enables flash, besides editing the build.prop. From the Google Play update log it sounds like its merely disabling flash on JB while still allowing it to work on ICS/GB, so the flash supporting part of Dolphin is still there, its just being disabled.
Motorola Droid 3
Android 2.3.4 (Stock Rooted)
UnOfficial CM10 4.1.2
Download Adobe Flash For Android: