Scott is absolutely correct that there's no way using the standard dice macro to do this. But you are a Pro user, so if you're the GM for your game you do have access to the API, and should be able to do this with a script. There's a powerful script called Power Cards, that has a thread in the API forum there. One if its users should be able to tell you how to do this with that script. I remember there's another script which monitors chat for results, and could probably intercept critical results and report the extra successes, but I can't remember what that's called. If they dont work out, one of the script writers here (like me!) will help you whip up a custom script to handle it when we have time, if you want to go that route.