I am trying to mine btg at suprnova and only get rejected shares, I use hiveos and mined at suprnova before the fork and worked fine, now I changed to new ewbf version, algo 144_5 and new port 8866 but I only get rejected shares, can anyone help me? 
Are you sure you added required parameter --pers BgoldPoW?
Just tried mining with this and it works fine for me (v0.3 of miner)
Quote
miner --algo 144_5 --pers BgoldPoW --server btg.suprnova.cc --user username.worker --pass 1 --port 8866