I've tried the cpuminer version 0.2.1 on a VIA Nano machine. I used the "via" algo with a bitcoin running on the testnet. The miner worked, but the results generated seemed to be wrong, debug output pasted in below.
The system is a 64bit Debian unstable machine with a VIA VB8001 motherboards. It's running a stepping 2 VIA Nano. The kernel seems to do a workaround for Nanos with that stepping, perhaps something needs to be done in the miner code, as well.
HashMeter(0): 16777216 hashes, 1589.69 khash/sec
DBG: found zeroes in hash:
9ec42e51b34b69fc2f7209f3e334afcfa563d1da21647832cd2b312c00000000
HashMeter(0): 6644792 hashes, 1606.76 khash/sec
PROOF OF WORK FOUND? submitting...
DBG: sending RPC call:
{"method": "getwork", "params": [ "000000016f643cccfaa9574cd1a3369a23da6452fcf296587e4da572a008520300000001f1071376c66751bede719672dd1e9e3b2a3daeec709fc5bcaede21364748d93a4cf93ea21d05106000000000000000800000000000000000000000000000000000000000000000000000000000000000000000000000000080020000" ], "id":1}
PROOF OF WORK RESULT: false (booooo)
Actually, it looks like it is working, to me. As explained
in this thread, cpuminer searches for an
approximate number of leading zeroes in the hash.
It then submits that hash to bitcoin, for final verification. Thus, it is normal for cpuminer to find several almost-solutions, before finding a real solution, depending on current difficulty.
The official bitcoin client works this way too -- it stops hashing when a certain amount of zeroes appear. However, it does so silently, whereas cpuminer print something.