FYI on using yum or up2date, the proxy_user and proxy_passwd variables and their GUI equivalents do not work trying to get through our proxy.
To get through our proxy these values must be set in the proxy address: http://username:password@proxy:port
Went through all the bugzilla reports, including patching some python file, blah blah blah and didn't see this anywhere - this was the trick.
If you want to see the error I was getting, someone else posted it this asian language page, the rest of which I can't read: http://www.linuxml.net/pipermail/fedora/2003-November/000117.html
I had an error trying to use an http repo with an error 401. I didn't have the problem with using an ftp repository though.
Is your problem with ftp also or just with http?
Jim