Login to an FTP proxy defined to CA CSM fails because the default port number (21) is being appended to the userid for the proxy in the format firstname.lastname@example.org:21.
. Resolved by build 88 so upgrade to the latest build 88. Using HTTPS download mode will work around the problem. Check the "Use HTTPS for Downloads" box in the Settings tab, System Settings, Software Acquisition. Be sure to click apply to save the change to the database.