CiviMail automatically attaches CiviGrant files to Mailing

After upgrading from 4.6.2 to 4.6.3, files that are stored in the civicrm_file table are automatically attached to a new mailing as soon as the mailing opens. You also cannot remove the files. You get the following error
"Failed to run permission check: Unrecognized target entity table (civicrm_grant)"

Steps to recreate:
1.) Enable CiviGrant, create a new grant and add at least two attachments.
2.) Start a new mailing and go the attachments tab and there will be two files that you just uploaded and you will not be able to remove them