Comparig 2 files in Netbeans - moving change changes depends on selection

In NetBeans 6.5, when you select one file in the project window and select a second with the Ctrl-key pressed, selecting the local menu with the right mouse button or Shfit-F10 lets you select the Diff Command in the Tools-Menu entry.

The two files are shown side by side and the differences can be moved from
the left file to the right.

The first selected file is shown on the left side, the second on the right side.
If you now recognize, that you have selected the files in the wrong order, you can
click the Swap in the Window-toolbar to exchange the position of the two files
shown in the diff window.

Before Swap:
After Swap: