Platform: Mac OS X, Java 1.5.0_13
GWT: 1.5.2
GXT: 1.0.1
Safari: 3.1.2

The following code displays badly in hosted mode.

Code:
  public void onModuleLoad() {

    Viewport viewport = new Viewport();
    viewport.setLayout( new BorderLayout() );
    
    LayoutContainer north = new LayoutContainer();
    north.add( new Html("North") );
    viewport.add( north, new BorderLayoutData(LayoutRegion.NORTH, 33) );
    north.setStyleAttribute("background", "red");
    
    LayoutContainer west = new LayoutContainer();
    west.add( new Html("West") );
    viewport.add( west, new BorderLayoutData(LayoutRegion.WEST, 100, 50, 250) );
    west.setStyleAttribute("background", "blue");
    
    LayoutContainer center = new LayoutContainer();
    center.add( new Html("Center") );
    viewport.add( center, new BorderLayoutData(LayoutRegion.CENTER) );
    center.setStyleAttribute("background", "green");

    RootPanel.get().add( viewport );
    
  }
Hosted mode:



If I press the "compile" button in the hosted mode browser I launch Safari and it looks correct:



Not sure if this is a GXT, GWT or Mac OS X specific problem.