If you have tried to download the build tarballs to a Windows machine, you have gotten corrupted tarballs. This was due to an error in the configuration of apache on eros.cis.upenn.edu. Apache was reporting these files as type text, with the consequence that Windows Netscape (and possibly Windows Explorer, though I haven't tried it) was helpfully inserting carriage returns after every newline.
I have corrected the apache configuration, and the download now works correctly.
If you have been downloading from a UNIX web client, this should not effect you.