for what it's worth, i don't think the problem is you.... it appears to me that the installer that downloads when you try to get 1.6b is exactly the same as the installer for 1.4b. (i happen to still have that one laying around on my hard drive, and the new one has the same size and creation date.)

i'm assuming it's just a mistake, but i've tried downloading 1.6b from three different sources, and keep getting the same old thing.