Danbi,
If you can take ANY other groestl coin (what..all three of them?) and have it work in a heart beat, which they do, its not the stratum, its the coin.
True, you can make other groestl based coins work, but this is only part of the game. There is other hashing involved besides groestl in DMD and the other coins.
Still hacking, but so far, we have two choices:
1. make DMD hash like the other groestl coins and fork (!) again.
2. Modify both stratum AND the miner and avoid the fork. I am currently working in this direction.