Here is a tool that can upload files to a ftp host with interval ranging from 1 second to almost infinite. It will not run on Win XP (XP is outdated and should be replaced). It require .net framework 3.5, and to be run on vista, server 2008 or newer. It is a 32bit software, and will run on both 32bit and 64bit computers. Check out the download page for FtpUploader for download link and more information.
Edit: It will run on XP, but will have to be installed manually without using the Installer.