Swing/AWT/SWT :: JTable Sort Numeric Column

I am trying to sort a JTable on an all numeric (integer) column. From what I read, if the sorter knows the type is integer it should sort correctly. This is my code:

public class ActorTableModel extends DefaultTableModel {
private static final long serialVersionUID = 1005352603826663105L;
public ActorTableModel (Object data[][],Object columnNames[]) {
super(data,columnNames);
}
public Class<?> getColumnClass (int column) {
if (column==0) {
return(Integer.class);
}
return(String.class);
}
}

The result is when I sort on that column (0), it sorts alphabetically not numerically.