[Zope] FTP issue or Alternative

Hello All, I am trying to FTP images into various zope directories. Some of the images show in zope as 0k. When I check these out in the file system they are greater than 0k and I can view them. So I put like a 5 second sleep in my script before every image is ftp'ed. This method did reduce the number of 0k files however it did not eliminate the problem. I do not want to use the use 5 second method as the scripts takes a very long time to complete. Is there something I am not aware of? What other method can I use? Can I simply take a OS directory structure and import it into zope? I am not sure how. Can you point me some sample code or literature. Your help or guidance is much appreciated.