For users behind a NAT firewall/router, there this is an obstruction to connecting to networks that require ident response and attempt to make the ident request from a server address other than the address the user is trying to connect to.
This problem can be overcome by the user's computer simply attempting to establish a connection with the other server that is sending the ident request.
Could mIRC have a setup in the network settings to attempt a TCP connection with a given server whenver attempting to connect to any server on that same network, to tell the users NAT firewall/router that you're trying to talk to that server (for ident request)?
Also, to establish DCC, similar connection attempts (although maybe failing) are required before the NAT firewall/router will permit the DCC recipient to connect to the user's computer successfully. An option to do that would be nice, too.