10.9 server keeps losing correct permissions on /private/tmp
Maybe resetting the permissions on a user's home directory helps: 
This is easily accomplished by resetting ACLs on the desired home directly by using the Reset Password Utility in the Recovery Partition:
    1   Restart your computer from the recovery partition (restart while holding CMD+R). 
    2   Open Disk Utility and run a permissions repair on your startup volume. After this is complete, close Disk Utility (doing this just for good measure).
    3   Open Terminal from the Utilities menu. Type in resetpassword and select your user account (NOT System Administrator/root) from the drop down menu. 
    4   Click the Reset Button at the bottom of the window in the Reset home folder permissions and ACLs section. 
    5   Quit the Password Utility and go back to the main recovery screen. 
    6   On your keyboard, hit CMD+Q and restart your computer. It's very important that you don't hold down the power button to exit the recovery session, or the ACL reset won't occur.