Yes... using AWT makes a difference... No ImageIcon class in AWT...
To display an Image in a frame you either have to override the paint() method of the Frame and draw your image there, or use another component ( like an extended Panel or Canvas ) to draw your image on, and then add that component to the Frame. I prefer the latter... Here's a class called ImagePanel that I just had lying around...
And here's a class that illustrates how to use it...
HTH,
-Nate