This is me. It's a wallet I created by sending approximately 250-500 PPC every 5-10 minutes over the period of a month. The actual amount and time depended on how much PPC I had available. I kept this running on a 24x7 node and it averaged about 150 blocks immature constantly after about 40 days. The machine it was on had a hard drive failure and it's been offline for a week or so. Having recovered the wallet from backup I've fired it up again and I guess it's catching up. For the curious the ppcoind node this runs on uses about 80% CPU idling - I assume that POS stack code takes a bit of CPU while cycling through so many transactions.
Hi Chris, when you generate these blocks which version of the client were you running? Is it the latest v0.3 client?
The protocol has been switched over to 0.3 today. The situation should improve gradually. Like Jutarul said, stake participation rate might have also contributed to the problem.
The average age of stake is meant to be eventually closer to 90 days than 30 days. In 0.3 protocol a change was made so that the weighting starts from 0 at the 30-day minimum age. This should help strengthen proof-of-stake protection when difficulty is still low.