ZIP Archive Issue

Hello, I am a newbie - not sure if this is the group I need to post
to. I am able to download both 1.6rc6 and 1.5.3 on Windows platform:
However, opening the archive throws an invalid archive message (use
Winzip). However, there seems to be no issues with dl/opening the
archive on RedHat. Any help would be appreciated.
Thanks
Sri