jFileChooser.setMultiSelectionEnabled(true) not enabling

I did exactly what it told me to do for allowing the usage and selection of multiple files. yet it is not allowing me to select multiple files from the JFileChooser GUI. I try holding down the mouse button to select, shift-click, ctrl-click, and nothing works. I am using JDK v6, so compilation is not the issue.

JFileChooser picker =new JFileChooser();

picker.setMultiSelectionEnabled(true);

int returnVal = picker.showOpenDialog(null);

if(returnVal == 0)

{

File[] selected= picker.getSelectedFiles();

...

}

[782 byte] By [Tweaklinga] at [2007-11-27 1:49:43]