Sessions proposal

I find PHP session lacking in one area. In my applications I typically want to have a long timeout for adminstrators so that they don't have to log in all the time. A typical value is 2 hours. For users I prefer 15 minutes, based on the assumption that a user will go in, do his stuff, and leave. For this to happen I need to have the gc_maxlifetime set to 2 hours, or risk unpredictable results for the administrators. The problem with this is of course that garbage collection will run infrequently for the entire system, even though most of the sessions expire after 15 minutes. It would therefore be nice to have something like "session contexts", where you could have different session settings for each context. Is this possible to achieve? Anyone else who can see the use of this? Regards. André Næss