How is your IRC client supposed to receive/log messages while you are offline? Right, it doesn't work. You might want to think about running an IRC client somewhere on a server (with remote desktop/SSH) and connecting to said server to chat. This way, the IRC client will always be running, and you could simply re-connect to the server at a later time and scroll up to read conversation. Alternatively, if the IRC server is run by your company, why not enable global logging server-side, and publish the logs on your internal network via HTTP, for example?