set ftp user without shell, but cannot login

[James D. Parra]

Hello,

Running proftpd on two machines. One has all the ftp users set with
/dev/null as their shell and they can get into their ftp accounts. 

Setup another proftpd server, but ftp users can only login to their ftp
accounts if they have a real shell account, /bin/bash, for example.

I would rather the ftp users NOT have valid shells. Any ideas on how to fix
this?

Thank you in advance.

James