The Browser Appliance was updated to run Firefox 3.6.7 on CentOS 5.5 .
You may now update Firefox 3.6 to the latest release from within the program itself by selecting "Check for Updates..." from the Help menu.
The latest Adobe Flash plugin can be installed from the Terminal using the command:
sudo yum install -y flash-plugin
You will then need to restart Firefox in order to use the Flash plugin.