I never use this feature, and just figured out how to turn it off:
1) Open the VNC server perl script.
2) Scroll down to approximately line 140. Find either of the following lines, and comment it out:
# $cmd .= ” -httpd $vncJavaFiles” if ($vncJavaFiles);
# $cmd .= ” -httpd $vncClasses”;
3) Restart the VNC service.
service vncserver restart
4) Verify that port 5800 is no longer listening with the command: “netstat -pantl|grep LISTEN”