The main reason for this delay must be related with 'httpping' feature from server's header but the real slowness appears within jan-feb this year. Httpping obviously is not related with Opera Mini development since is hard to find a mini server with port 80 open (8081 is always open but not for ping-pong), instead it has something to do with ISP gateways behaviour as secondary (bad) behaviour. Most likely this 'ping' mask all open ports for debug consoles (run on latest line of products) running only on devs play field.
Opera Mini
