I switched to Hashcows since H2O doesn't seem to be willing to fix the problem. There definitely is something wrong with the pool and he just doesn't acknowledge.
Look at the top address. Just made .4 today when usually his balance is above 1, maybe 2 BTC per day.
Looks like H2O doesn't want to earn money anymore
It's funny - I switched to hashco.ws for what appeared to be "more service". The only problem I had with middlecoin was the occasional stall when switching coins - which was the same on hashco.ws (actually it was more frequent). I found a newer version of cgminer fixed that problem, and switched back because the profit is higher and I feel more comfortable with the presentation of the numbers on middlecoin (immature, unexchanged, and current btc balance) vs. a single number of an "estimated" payout. You'll like the cows, their profit is about the same, maybe a smidge lower on average.