It is possible that the server is waiting on an identd response.

Use this command: /identd on <username>

Keep the username to alpha-numeric text with no special characters. Also, make sure port 113 is correctly forwarded if you are behind a router and that any firewalls you might have are instructed to open it.

Another option is to try another port. 6667 is pretty common. Most IRC servers use a range from 6667 to 6669 and 7000. Try another port.