Ftp problem on proxy server

Hi all,
First of all i would like to say sorry to all for my english.
My name is Mastan. We have an proxy server have 2 lan cards. one is for public and another for private.

public ip: 182.72.141....
private ip: 192.168.0.0

So, the thing is i configure ftp server in my local for uploading and downloading the files. It's working fine. But when i login to my dedicated server through ssh the ftp server is not working.
for private i put like this.

ftp 192.168.0.1

and for public i put

ftp 182.72.141....

private is working but from the public i cant access the ftp srever which it is located in local. what is my problem .
please any body help me.