Sorry, no. Zenphoto is being prevented from creating the file. I would seriously consider getting a different provider. SAFE MODE is both not safe and not conducive to many scripts because if prevents what should be considered 'normal' operation.
See http://us.php.net/features.safe-mode
and http://www.breakingpointsystems.com/community/blog/php-safe-mode-considered-harmful
Looking at where the failure occurs, it might be possible for you to bypass it by insuring that the permissions on the backup folder are relaxed so that Zenphoto is able to read/write/execute the folder.