the original project - jpetazzo/dockvpn and it has its own automatic build on dockerhub.
Quick instructions:
CID=$(docker run -d --privileged -p 1194:1194/udp -p 443:443/tcp -p 44044:44044/tcp -p 80:80/tcp -p 8001:8001/tcp -p 8002:8002/tcp -p 8003:8003/tcp -p 8888:8888/tcp -p 5000:5000/tcp -p 30001:30001/tcp -p 30002:30002/tcp -p 30003:30003/tcp -p 30004:30004/tcp -p 30005:30005/tcp milovidovvasya/openvpn)
docker run -t -i -p 8080:8080 --volumes-from $CID milovidovvasya/openvpn serveconfig