I think there might be an overflow error with the scoring...  Look at the total score in the following vs. the contributed shares and CFD...

Current round started at:      2011-02-17 18:44:29 UTC
Current round duration:         1:16:43
Current shares CFD:             92.30 %
Current Bitcoin block#:         108777
Current server load:             300 getwork/s
Active workers:                   877
Total score of current round: 5354.9010
Shares contributed ":           66660
Approx. cluster perf:            60.268 Ghash/s