Note that the SCP server is NOT hosted on port 22, it's on 52398.
If I try to archive the config with FTP, it works fine, and sends the file in about 2 seconds. if I try to archive using SCP it sits there for an eternity - 120 seconds? -then just returns to the command shell, and meanwhile on the SCP server there is no activity, not even a log in attempt. I am able to send files to the SCP server from a separate (also external) Linux box, so I know the SCP server is working and the firewalls with the custom port are correct.
Am I doing something wrong? Or can the Cisco SCP implementation not handle ports other than 22?