Siebel 8.1.1.9 High Interactivity application, mouse pointer issue

Hi,

we are currently using Siebel 8.1.1.9 High Interactivity with IE8 and i was testing IE9 in compatibility mode ( i know its not supported but just wanted to see how it behaved).

For the most part the Application works fine in IE9 but i have noticed one strange issue, that is 

From any button click that takes over 3 seconds to return what I can see is that once you click the button the egg timer appears and after about 3-4 seconds the cursor changes back to the pointer, yet the application is still processing in the background (and if you attempted to click on anywhere else on the screen you would get the “Your browser is not responding” type message), then once the processing has finished you can work away again as normal.