--- Operating System, Graphics card ---
all

--- Blender version with error, and version that worked ---
2.68a

--- Short description of error ---
Defining rotations parameters for the particle system is taken into account when using the particle instance modifier, even after unchecking rotation in the particle system panel.

--- Steps for others to reproduce the error (preferably based on attached .blend file) ---

1) open the attached file
2) uncheck "rotation" in the particle system options.
3) Nothing happens, only checking it again and manually give the default values for each parameter kind of "disable" it