public class MyViewPart extends ViewPart {

  ...

  public Object getAdapter(Class key) {
    if (IPropertySheetPage.class.eqauals(key)) {
      PropertySheetPage myPropertySheetPage = new PropertySheetPage();
      myPropertySheetPage.setSorter(new MyPropertySheetSorter());
      return myPropertySheetPage;
    }
    
    return super.getAdapter(key);
  }
}

class MyPropertySheetSorter extends PropertySheetSorter {

  public int compare(IPropertySheetEntry entryA, IPropertySheetEntry entryB) {
    // your custom sorting
    return 0;
  }
}