samba - Apr 2014 - Need help with variable substitution in smb.conf

Hi,

We are using Samba to serve GlusterFS storage, below is the entry for the same
in smb.conf:
[gluster-vol3]
	comment = For samba share of volume vol3
	path = %P/sub_dir
	read only = No
	guest ok = Yes
	vfs objects = glusterfs
	glusterfs:loglevel = 7
	glusterfs:logfile = /usr/var/log/samba/glusterfs-vol3.%M.log
	glusterfs:volume = vol3

When path is defined as "%P/sub_dir", Windows 7 client fails to
connect to the share, tried 'max protocol = NT1/SMB2', 'msdfs root =
yes', 'host msdfs = yes' but would still not connect to the share.

If the path is defined "/sub_dir" without %P, everything works well.
But we need %P to get the subdirectory export working, else CTDB complains that
the export was not found on the local system.

Any inputs on why %P would not work or any other workarounds would be very
helpful.

Thank you,
Poornima