Openfire group sharing (only online users)

Hi,

Is there a way to share just those contacts of a group that are online and automaticaly update the list when a user is loged in or out. There are at least 10.000 users and there are only ~50 online at a time. Sharing a contact list with so many users seems unreasonable. Also when I try to open the group section on web-backend it overloads openfire dumping a heap overflow error.

Not out of the box. I’m not a developer, but it seems to be possible with a custom plugin or like that.