FTP - Simple upload incurs hundreds of connections?

[jols]

What would cause a simple FTP connection to incur hundreds of connections? We have one customer who gets blocked by our ddos stuff all the time. We see logs like this:

Banned the following ip addresses on Wed Nov 22 09:27:01 CST 2006
70.xxx.xxx.xxx. with 270 connections

Any idea?

 

[Infopro]

Came across this as well recently. He was using freeftp? or something, I suggested he switch to CuteFTP and the issue with his IP ended. Would like to know more about the problem myself.