Are you sure this format is correct? It does not look good to me:
rpcallowip=::/0
You could try something like:
rpcallowip=*
or (for better security), something like if you are testing it from your LAN:
192.168.0.0/24
(depending on the addresses).
Or you could just whitelist your IP.
What did curl show - as cassini suggested above?
rpcuser=username
rpcpassword=password
rpcallowip=::/0
rpcport=8332
server=1
rpcallowip=::/0 - ONLY TO OPEN ALL FOR TESTING....
Even with specific IP it dosen't work (Again other coins does NOT have issues)