You need to be root to bind to a privileged port. Try starting Fisheye as root, or better yet, leave the Fisheye configuration alone and set up a reverse proxy server ahead of it.
I would not recommend running any Java application as root. If there is a Java vulnerability that allows an attacker to run arbitrary code, it will run as root and make it trivial for someone to take over your server. Using a reverse proxy allows you to leverage the smarts of the proxy to bind to 443 as root and then spawn child processes running as an unprivileged user to manage the connections, which is far more secure.