If others shall see your current away time every time they perform a /whois on you, and as the whois information isn't sent by you but the IRC server to the person doing the whois request, the script has to update your current away reason (technically it has to send a new away reason to the network), say, every minute.
The script has either to override the default away command, or (preferrable) be triggered by different means (custom command, popups or the like). Anyway, it has to store the away reason you give, and run a timer for the time you are away (as long as you are marked away, until the "back" raw is received), which does the update thingie. Other catchwords may be "multiserver" and "resume after reconnect"...
Do you set your away manually at the moment, or do you use a script or multiple scripts to go away (some autoaway script, away/back via popups, a custom away command...)? If you already use some scripted away, pleae try to find the relevant code parts and post 'em.
