Description of problem:
On rare occasions when asynch communications take longer than the 10s processing limit the client/server currently throws a request timed out exception(We should review if this is truly the desired behavior. See below).  This appears to happen for FF, but not consitently for Chrome or IE.

Version-Release number of selected component (if applicable):
RHQ 4 Test build master 1143

How reproducible:
Almost every time on a server where asynch activities are slow.

Steps to Reproduce:
1. Browse to a Resource>Activity Dashboard and add several more dashboard portlets to slow overall load time.  Use F5 to completely reload the browser, then CTRL+SHIFT+S to view load times with an eye on Message Center.
2. On IE8 and Chrome 10.0.648, using CTRL+Shift+Alt+S, the attached screen shots show asynch operations that take longer than 10000ms, but no operation timed out messages are generated or show up in the Message Center.  
3. See attached screen shots for more details.
  
Actual results:
FF detects timeouts correctly, but IE8 and Chrome do not most of the time.

Expected results:
Consistent timeout or no timeout across all browsers.

Additional info:
On FF where the browers is forced to timeout correctly, the user experience is significanlty worse as the left nav tree will fail to load or disjoint error messages will pop up.  Page is in pretty bad shape after timeouts, wheras IE and Chrome do take a little longer to load but leave the UI in a usuable and correct state.