System Information
Ubuntu 15.05

Blender Version
Broken: 2.75

Drivers are run before being added to drivers namespace from reg'd textblock when running blender in bg mode.
as detailed here http://blender.stackexchange.com/questions/36511/drivers-not-working-when-running-blender-in-the-background-from-command-line

running the following on attached blend
blender -b -y <pathto>/x.blend

or

blender -b -y <pathto> /x.blend --python-text x.py

produces the following

read blend: /home/batfinger/Documents/x.blend

Error in Driver: The following Python expression failed:
'x(frame)'

Traceback (most recent call last):

File "<bpy driver>", line 1, in <module>

NameError: name 'x' is not defined
RUNNING x.py in x.blend
is driver valid False
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