I'm taking the opportunity to make a quick test post (experimenting with browsers - I am always without fail hacked on this page!) while bringing this log up to date. I've taken the problem over to a thread on the Fedora SELInux forum which can be found here:
mouse pointer stuck in browser sandbox window
I also moved from SL6 over to Fedora 15 to try a current browser version out (SL6 is still using FF 3.X releases). The same bugs result though.
In a nutshell, with an install that should not have (at least in theory) been breached by an attacker gaining direct access to the keyboard, hackers can still hack the browser (running in a SELInux sandbox) -- but they don't seem to be able to hack the webpages so the encrypted VPN connection seems to be holding out - it is hacks like locking the mouse in the sandbox window, and crashing flash, that are getting through (I am fairly well sure at this stage that these are hacks).