Presuming that the OpenVMS server has had the ftp daemon configured and launched via TCPIP$CONFIG, this is likely a generic question around the usage and limitations of ftp in modern networks.
If the OpenVMS ftp daemon is running (and barring a degenerate error), then you're almost certainly being blocked by one or likely two firewalls; by port blocks on the ephemeral port range. These blocks are typical and common, because few security administrators wants to have the whole range scanned, and fewer folks have firewalls that can open the proper ports by sniffing the ftp traffic.
http://labs.hoffmanlabs.com/node/530ftp is good for old stuff and for local stuff, but the protocol inherently stinks around firewalls and modern networks and modern network security.
Here? Consider using sftp. (Via Filezilla, if you're using Microsoft Windows as a client, and your version of Windows lacks sftp tools.) sftp is vastly more easy to punch through a firewall, and it's more secure, and you can set up a passphrase or even a no-password login. Or use a VPN and route all of your traffic to the remote server over the VPN, if you really want to use ftp.
