FTP server info access problem.

[Supertastic Fool]

Ok, I have my FTP server up. I'm using bulletproof to run it with. I have my directories listed and stuff and when I log in from my computer it shows all the files. When I try to have someone else test it though it says in bulletproof cannot open data connection and does not show the files for them? Anyone know why this could be?

 

[Heisenberg]

Firewall problem?