I have a quite powerful server which pretty much sits idle and I thought I'd use its cycles for some pool mining with cpuminer. However, nothing seems to get accepted. I tried two pools (bitcoin.cz and bitminter.com) but it's all the same.
Here's the error I'm getting on bitminter:
[2013-12-07 08:56:04] < {"result":null,"error":[23,"Below difficulty",null],"id":4}
[2013-12-07 08:56:04] accepted: 0/209 (0.00%), 45.88 khash/s (booooo)
Any hints?