I wrote the following short script:

from ftplib import FTP

ftp=FTP('ftp.edsanville.us', username, password)
print ftp.getwelcome()
print ftp.storbinary('stor test.xls', file('test.xls',
'r'))

ftp.quit()

It transfers the entire file under Red Hat Linux 9, but
under Windows XP, it only transfers a couple kilobytes
at most.  Using a hex editor, I found that the first 5
or 6 bytes of the file are OK on the remote side after
transfer, but the rest of the file is totally wrong. 
I'm at a loss, it doesn't make any sense.  Please,
somebody tell me I'm not insane.