csync breaks file permissions syncing between rep1 and rep2

[halkyon]

Example scenario: deploy the same revision to two machines, rep1 and rep2, then halt rep1 machine. Deploy a new revision to rep2, then bring back the rep1 machine. csync eventually pushes the files from rep2 to rep1, but it breaks the permissions of the /sites/mysite/releases/* directories on rep1. The directories are now owned by root, and only readable by root.