How do I let a DataWindow know it isn't frozen?

I've got a little utility (infomaker frontend) driven by a stored procedure that has to wait around for about a minute while other processes it triggers are completed. Whenever I run this utility, the application becomes unresponsive until the procedure completes.

What do I need to do in my stored procedure for the client application to know that it's still alive, and display a progress bar as the procedure completes?