Didn't work and I got the error: 502 'PORT' command not implemented.
That looks like an FTP server that insists on passive mode. That's generally a good idea.
I solved the issue by putting the entire connection into PASV mode
That confirms this. Generally, passive mode is the prefered way to communicate with an FTP server. http://slacksite.com/other/ftp.html explains the difference between active and passive mode quite well.
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)