Fixed issue where PropertyChanged is raised for Isbusy and Model even if the value didn't actually change.
Fixed issue where PropertyChanged is raised for Isbusy and Model even if the value didn't actually change.

MarimerLLC/csla,rockfordlhotka/csla,rockfordlhotka/csla,JasonBock/csla,rockfordlhotka/csla,JasonBock/csla,JasonBock/csla,MarimerLLC/csla,MarimerLLC/csla