[Plugin: cbnet Ping Optimizer] Cbnet Pinger doesn´t work

Hello,

I logged into my wp blog and recognized, the ping plugin hasn´t pinged for several days now.
Does anyone have an idea, how and why this happens?

Thanks for support
Bo

http://wordpress.org/extend/plugins/cbnet-ping-optimizer/