My existing app was really happy with files, in my tree control,being sorted a-z and headers taking up the entire width of the control.
Upon converting to 2008 my files are sorted z-a and the headers take up onl 5-10% of the width of the control. If you click on the headers, they will then rapidly expand to fill the entire space and which ever header you click will of course, cause a sort to occur...
You should Submit an incident to Infragistics Developer Support and provide a sample demonstrating the behavior if possible.