It's not possible to mine this coin due to a bug in the client.
04-Jan-2014 07:20:59 height: 221630 mint: 0 difficulty: 0.00024759 flags: proof-of-stake
04-Jan-2014 07:34:00 height: 221631 mint: 50 difficulty: 0.0518714 flags: proof-of-work
04-Jan-2014 07:22:20 height: 221632 mint: 50 difficulty: 0.00799874 flags: proof-of-work
Block #221631 has a timestamp which was ahead of the network. The code in the client which calculates time between blocks does not handle the special case of the timestamp of the previous block being higher (rather than lower) than the current one.
Since we're all running that buggy client the network is stuck in proof-of-stake mode only.
This same problem has happened to other coins such as ORB and ADT.
It will need a dev fix / hard fork to get the network going again.