I don't know if you are still looking for a solution but if 
you are, here is a quite simple way : visit the page with 
the java applet with Internet Explorer, wait until the page 
is completely loaded, then look for the files in the  
Temporary Internet Files folder, copy all the java 
(.class, .jar) files in their respective folders in your 
mirror, rename the files by deleting [1] in the filename.
If it doesn't work, modify the path (value most of the 
time) in the html file(s).
Good luck