Flash detection script does not work!

I just read a tutorial and tried out the flash detection script featured on the Kirupa forum: http://www.kirupa.com/developer/mx/detection.htm.

However when I tried to impliment it, it let me through on a computer that does have flash 8 and on a computer that does not have flash 8. Is the script outdated?

I know that the script should work, becuase when I visit gotoAndLearn.com on the computer without Flash 8, it will not let me in.

Any thoughts?