Exportig Work Items from query to csv in Web UI

Hello,

There is a problem with exporting Work Items from query to csv file in Web UI.
Steps to reproduce:
1. You need to have some PA with some WIs
2. Open Web UI
2. Run some query (e.g. New unassigned from the predefined queries set) - lets say that the query returns 3 WIs
3. Export the Work Items from the query to csv file (top right corner, next to refresh button)
4. Download and open the exported file - you should see 3 WIs
5. Add new WI (make the attributes appropriate, so that this WI will appear in the previously used query)
6. Run the same query - you should see 4 WIs
7. Export the query result to csv file
8. Download and open the file - you will see 3 WIs again! instead of four!

Now the strange thing:
This can be reproduced with FF 3, and cannot with IE.
The above scenario works in RTC Eclipse client.

Any ideas why the newly added Work Items are not exported properly?

Thanks for you help!
Jakub