Oh, that's bad. That means Tor isn't trying to reach the server. As Hash said, there could be some problem with mIRC. I was able to get mIRC to connect when I tested it in a Windows VM, but who knows. You could try with Pidgin. Pidgin works well with Tor. It even has a Tor mode. Use all the same configuration settings except use the onion address for server, not the IP address. Remove the mapaddress line in torrc. In the proxy settings, use Tor/Privacy (SOCKS5) instead of the SOCKS5 option.