How to unload FCKEditor instance at runtime?

I'm working on a big project using HttpRequests to get data and use this data (html + runtime parsed JS, similar with FCK script file loading) to create inline popup windows (div's; I try to make a gMail like app, used over ssl - explorer don't cahe anithing - so, loading all JS in one piece - on start - will help me allot).
One of this window contain a FCKEditor instance. It must initiate a FCK instance at runtime (when this window content has been loaded via HtppRequest). When this window is closed (no page refresh in browser) I need to de-alocate all memory/events. How can I do this? Please help...