The 2.0.3 under oacs-5-1 has never been tested to my knowledge.
In fact, the instructions I put up above for the oacs-5-1 branch is probably pretty close to the 2.0.3/oacs-5-1 combination since adding oacs-5-1 accounts for most of the changes.
I'd say the best bet is to fix the oacs-5-1 branch so we are that much closer to a stable release with the oacs-5-1 fixes.