Upload to another server

Hi there everyone, I was searching for this question, but I couldn't find exactely my problem.

So here is:

- I developed an CMS site that manage another sites. This site (PHP) is in the server X.
- The sites managed by this CMS it's in another server, the Y server.

This works:
When I set the $baseUrl and $baseDir in the same X server that my CMS site, the upload works fine, incredible! Example:
- My CMS site is: http://mycmssite.com (URL in the server X)
- $baseUrl: http://mycmssite.com (URL in the server X)
- $baseDir: /mnt/data/var/www/sites/mycmssite.com/ (URL in the server X)

This don't work:
When I set the $baseUrl and $baseDir to the Y server, I receive the "116" exception (CKFINDER_CONNECTOR_ERROR_FOLDER_NOT_FOUND).
- My CMS site is: http://mycmssite.com (URL in the server X)
- $baseUrl: http://thesitemanagedbythecms.com (URL in the server Y)
- $baseDir: /mnt/data/var/www/sites/thesitemanagedbythecms.br/ or http://thesitemanagedbythecms.com (URL in the server Y)

I was thinking in two possibilities to solve this... One is move the site that is in the Y server to the X server.
Another (that I don't have any idea if it's possible), is to change the CkFinder core to open a FTP connection to the server Y and upload the images there.

Someone alrealdy had a similar problem or have some idea to help?

Thanks in advance!