LVS_NOSORTHEADER problem in Win7

[12oclocker]

Win32API (no MFC) in Windows 7
once a listview control is created, if I add the style LVS_NOSORTHEADER, it has no effect, is does not disable the column buttons. Anyone have any ideas?

//Code is in OnInit dialog, and does not work
HWND hList = GetDlgItem(hwnd,IDC_LSV1);
LONG stl = GetWindowLong(hList,GWL_STYLE);
SetWindowLong(hList,GWL_STYLE,stl|LVS_NOSORTHEADER);