IrcDotNet and Quit event

I am making an IRC client using IrcDotNet.

I am having problems with the IrcUser.Quit event, which is not always being called, leaving me with ghost users in my nick list.

I see in the source (see below) that its not always sent. How do you handle the users quitting so that the nick list is always accurate?

thanks.

    /// <summary>
    ///     Occurs when the user has quit the network. This may not always be sent.
    /// </summary>
    public event EventHandler<IrcCommentEventArgs> Quit;