Shoutbox

To detect when someone clicks the column header, you don't have to write a dll to subclass the ListView at all. ListView controls send a WM_NOTIFY message to the parent window for various events, including when the column headers are clicked, which means you can detect it in JScript using PlusWnd.RegisterMessageNotification().

I have attached a little example script to detect column header clicks, enjoy

Note: if you have multiple ListViews, you can distinguish between them by reading the hwndFrom of the NMLISTVIEW structure.
if(NMLISTVIEW.ReadDWORD(0) == Wnd.GetControlHandle("<ControlId>"))...