IWDatacapture.displayMessage (message)

System

I have an onSave handler in my template that takes some time to run. I would like to display a message to the user so they know the system has not locked up and what it is doing. I would like to avoid alert/confirm so they don't have to ack. I am trying IWDatacapture.displayMessage (message) but it doesn't write my message until *after* my handler completes (not when I call displayMessage) - even if I do an IWDatacapture.redraw() right after displayMessage. How can I force my message to display, other than putting it into a DCT item or using a popup of some sort?