Browser refresh breaks browser history in a Silverlight App

I've got the Silverlight app with 4 pages(wizard). Usually user goes throught these 4 pages from /1 to /4. Navigation is implemented using Silverlight Navigation. There is a strange bug under some IE8 and 9, when user press Refresh or Forward/Back button.

In example user navagated to /1, then to /2, then to /3 and press refresh. He sometimes gets redirected to page 1. If I open the history, it contains only page /1, but I expect all three pages - /1,/2,/3. Another way to reproduce is having been navigated to /3 press back, forward in the browser . This way history becomes broken the same way as described - it contains only one page and current pages is /1 instead of /3.

Can anyone tell me, what is the reason of such behavior and how to f开发者_如何学JAVAix this bug ?

http://files.rsdn.ru/3693/SilverlightNavigationApplication.zip

The main thing, that bug is reproduced on some machines with IE8 and IE9

There were a lot of exceptions in the deep of silverlight. When I turned break on exceptions and fixed the reason all works fine.