The purpose of this change was to prevent XML uploads from being used to arbitrarily initiate connections from the host system – likely behind a firewall – to user-specified URLs.
If you want to specify remote URLs in imports, use the command-line import tool; if you have command-line access, invoking HTTP/HTTPS connections from an import document does not represent an escalation.
Regards,
Alec Smecher
Public Knowledge Project Team