new remote server verification fails to create server-specific directory

For some reason, /var/aegir/config/foobar isn't created properly here:

Webserver custom pre-configuration ownership of                                                               [message]
/var/hostmaster/config/server_web1aegirdevkoumbitnet/apache/pre.d has been changed to hostmaster. [0.4 sec,
7.93 MB]
Webserver custom pre-configuration permissions of                                                             [message]
/var/hostmaster/config/server_web1aegirdevkoumbitnet/apache/pre.d have been changed to 700. [0.4 sec, 7.93
MB]
Webserver custom pre-configuration path /var/hostmaster/config/server_web1aegirdevkoumbitnet/apache/pre.d is  [message]
writable. [0.4 sec, 7.93 MB]
Executing: rsync -e 'ssh ' -azv --exclude="*.svn*" --stats --progress --omit-dir-times --delete                [notice]
'/var/hostmaster/config/server_web1aegirdevkoumbitnet/apache/pre.d'
'hostmaster@web1.aegirdev.koumbit.net:/var/hostmaster/config/server_web1aegirdevkoumbitnet/apache' [0.4 sec,
7.94 MB]
  sending incremental file list
  rsync: change_dir#3 "/var/hostmaster/config/server_web1aegirdevkoumbitnet" failed: No such file or directory (2)
  rsync error: errors selecting input/output files, dirs (code 3) at main.c(632) [receiver=3.0.3]
  rsync: connection unexpectedly closed (9 bytes received so far) [sender]
  rsync error: error in rsync protocol data stream (code 12) at io.c(635) [sender=3.0.3]
/var/hostmaster/config/server_web1aegirdevkoumbitnet/apache/pre.d could not be synced to remote server      [error]
web1.aegirdev.koumbit.net. Changes might not be available until this has been done. (error: sending
incremental file list
rsync: change_dir#3 "/var/hostmaster/config/server_web1aegirdevkoumbitnet" failed: No such file or
directory (2)

In fact, I don't see where that directory is created at all in the log. To add to the confusion, the apache.conf file transfer actually creates this... as a file!

Template loaded: /var/hostmaster/.drush/provision/http/apache_ssl/server_ssl.tpl.php [1.75 sec, 8 MB]          [notice]
Generated config encryption enabled webserver configuration [1.75 sec, 8.01 MB]                               [message]
Executing: rsync -e 'ssh ' -azv --exclude="*.svn*" --stats --progress --omit-dir-times --delete                [notice]
'/var/hostmaster/config/server_web1aegirdevkoumbitnet/apache.conf'
'hostmaster@web1.aegirdev.koumbit.net:/var/hostmaster/config/server_web1aegirdevkoumbitnet' [1.76 sec, 8.01
MB]
  sending incremental file list
  apache.conf
        1396 100%    0.00kB/s    0:00:00 (xfer#1, to-check=0/1)

fun fun, just before a demo. :)