This is the testnet checkpoint. There seems a bug somewhere allowing you to enter this state. Did you use the testnet at some point and what's the sequence of operations/events related to using testnet? Are you running a testnet node right now with main net node?
You know what, yeah I think I know how it happened, I'm messing around with the client to build a p2p pool, and I'm using the testnet flags and variables to let it know if its running as a pool node or a regular node.
However it still shouldn't have entered this state even though you operated testnet mode.
I deleted the blockchain folders and redownloaded it. And the issue went away so the issue was probably related to identifying the blocks.
I'm not even sure how to test if it was my modifications or not that caused it.