FTP won’t upload but downloads

Here is a good on for you to think about. I am running Win98se and am connected to the Internet with a PacBell DSL line using PPPoE. In running an ftp connection to our corporate server over VPN connection, I can upload, delete rename and change attributes on server files. If I try to upload a file, I get about 8K to move then the connection slowly tapers off until it stops. I am using CuteFTP as a client and NTS Enternet300 for PPPoE.
I have had quite a time trying to Make ICS work with PPPoEand Enternet even though they claim it supports PPPoE and ICS. Anyone have any thoughts?