Thank you for your reply which was really quick...
But I am using simpleminer on Win 7 x64 since I dunno anything about nix and compiling of cpuminer-multi etc.
6 threads, Core i7 920 and with 75% of utilization gives me around 75 H/s... but it is going up and down like on other pools, but not like this. Mostly around 50 H/s... I see the pool's hash-rate acts the same, falls over 10 times from 50 KH/s to 6 or so... So this problem must be hitting others too...
:/
yes i have spoken to some of the other pool ops and it is a global issue.
i can tell you that everyone involved is working on it.