I meant to type Mhash of course as I mentioned it's a HD6850
I have no idea what kind of stales they are, the p2pool application does not report anything that seems relevant. Also the amounts of rejects is see reported by my miner are vastly lower than these very high stale percentages.
Look for these line in the p2pool output:
2012-02-01 13:25:32.973102 Pool: 147GH/s in 17310 shares (17314/17314 verified) Recent: 1.39% >2045MH/s
Shares: 180 (8 orphan, 5 dead) Peers: 39 (29 incoming)
2012-02-01 13:25:32.973229
Pool stales: 8% Own: ~7% (4-12%) Own efficiency: ~101% (95-103%)The red part tells you how many and what kind of stales you are getting. The blue part tells you how that compares to the pool as a whole.