Fixed Flash detection for Opera / Wii

Some folks over at the Jangaron Tron-Sector thread reported that version 0.5 does not work in certain browsers and under certain circumstances.
The good news: I fixed a bug in my Flash detection code so that it now works in Opera without the right (and still without any) Flash plug-in. That fix (version 0.51) should make it work on the Wii, too ("work" in this case means "no sound, but at least you can play the game").
Concerning other browsers, some people seem to have tried IE6 and very old Safari versions which I cannot test, and both do not work. Let me quote from my own post over at Tron-Sector:

Jangaron is based on CSS border slants, which are not fully functional in IE6. One crucial feature, namely transparent borders, is missing in older IE versions, and Jangaron heavily relies on that feature.
Besides Firefox and IE7, there are many other alternative browsers that are supported by Jangaron: all other Gecko-based browsers should work (Iceweasel, Netscape, Camino, ...), Safari 3.1 (I think 3.0 also, but I am not sure) and other WebKit-based browsers, Opera 9.25 and thus the Wii browser. Unfortunately, there are still problems with browsers based on KHTML (the WebKit predecessor), like Konqueror 3.x. Jangaron's stable version seems to run on Konqueror 4, though, because some serious bugs in KHTML's JavaScript engine were fixed (or was it even replaced completely?).
Jangaron's claim "The Tron Lightcycle Game in any modern browser" is to be emphasized on modern, and is also rather a vision than a completely proven fact. I need help for testing and debugging Jangaron in this multitude of browsers, so all you JavaScript / DHTML gurus out there, feel welcome to support!
Thank you for starting to report problems; now, let's analyse and fix them if possible!