After clicking on the animation, a new browser window is launched. In this child window, go to a another page containing a applet. Now click on the animation. Notice in this child window that the java.com will replace the loading applet. This behavior does not seem correct. Shouldn't a new browser window be opened, even when clicking in the animation of a child window.

Just an idea, instead of using "Java_COM_Frame", how about generating a number using Math.random() in place of it. This way, each graybox instance will have a unique child window for java.sun.com. You could generate a random number using Math.random in the initialization part of the code, so that it only happens once. You can then use that number instead of "Java_COM_Frame". This way every time the graybox gets loaded there will only be one new child window for that instance. So, a user can click multiple times in the graybox and there will only be that one window. Plus, the child window itself will also be able to generate another new window of it's own. So, if the user changes the address from java.sun.com to some other page containing a applet, it will open up another window of it owns to show java.sun.com, instead of just replacing the window where the applet is on.

However, the drawback of this would be for pages containing multiple applets, since there would be one new window created for each applet.