Delegates and UpdatePanels

Hi everyone,

I have a page with multiple UpdatePanels (UpdateMode Conditional).
I'm having a concurrency issue:

1- The user triggers an Update on a panel to change some business data.
2- The panel is changing the business layer (in session)
3- The business layer is triggering (Invoke) a delegate to notify every
listeners that some business data have changed
4- Another update panel that was listening to the delegate in #3 is updating
its display to show the latest data

The problem is that the Panel in #4 has the new data but it seems that the
Panel has already rendered itself. So the user is seeing the old data but
when I refresh the page, the panel shows the live data.

I'm doing something wrong here (logic or programmatically). So where can I
find infos on this?
How would you guys proceed?

Just to let you know.. the UpdatePanels don't know the existance of others.

Thanks

Mike