Failed to Import Media - Remote server did not respond

I am trying to move sites from one server to another in a Multisite setup.

Both servers are Ubuntu 12.04 with Wordpress 3.5.2. Prior to the 3.5.2 update I could go to a subsite on server1 and export all content and import it to the new subsite on server2 and it would import all content no problems. This was done using the standard import/export plugin version .61.

After the 3.5.2 update I get all kinds of errors with "Failed to Import Media - Remote server did not respond" to and from server1 and server2. I have tried importing/exporting from each server in both directions with no luck.

I have a third WP multisite install WHICH WAS NOT updated to 3.5.2 and it can import media files to a subsite from each of the two 3.5.2 servers with no issues. However, I cannot import from the NON3.5.2 server to any of the 3.5.2 servers.

Can someone else verify there might be a media import issue with WP3.5.2??? Or point me in the right direction to fix this.