I just did the Java 7u9 update. When I clicked on the icon of an existing JAWS run using 7u7, it said the icon was not pointing to anything anymore, do you want to delete? I did.
I started it, using Firefox. It started from cache, but I did not get a new icon.
Deleted from cache, and starting once again, it downloaded & made an icon.
It seems to me, there was a lack of testing of effects on existing Java 7 JAWS apps. Right now on Windows anytime a jar resource changes the icon moves. I assume the old is deleted and a new created. Maybe that is what should happen every version upgrade.