New Post: Message Box ShowDialog

I want execution to stop when I show a message box. Per the documentation under Method:
"ShowDialog" "Display the MessageBox window and returns only when this MessageBox closes. "

When I try this I get the error:
"Invalid Operation Exception was unhandled"

"An unhandled exception of type 'System.InvalidOperationException' occurred in Xceed.Wpf.Toolkit.dll"

"Additional information: This method is not intended to be called while displaying a Message Box inside a WindowContainer. Use 'ShowMessageBox()' instead."

Is there a way to get around this? It looks like is it just the way it works and the documentation should be changed.