I have a @#!@#!@#!@#!@#!x running on background and I having problem receiving files from friends. I keep getting the below error
DCC Unable to create connection: Interrupted system call
I think it's due to my firewall blocking unused ports

Which port does dcc needs to be open?

See: http://www.irchelp.org/irchelp/rfc/dccspec.html

Adding the IRC module to your iptables setup should be sufficient, though

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