Essentially a couple people were able to mine a few block on the SHA algo. However since these coins are on a separate chain the existing network is rejecting them. The few people who did download 3.0.0 can see these blocks, but we are recompiling the wallet with a fix as we speak to v 3.0.1

We are implementing a checkpoint on the old chain that will invalidate all the SHA blocks. Stay tuned, and who ever is mining the SHA blocks please note they will be rejected by the old chain and will be invalid if you try and send them anywhere.