After I have applied a simple deform modifier, e.g. bend, the direction of hairs are wrong (not all along the face normals). In the illustration below I have created a cube, and subdivided it to allow it to bend (left). I then applied the simple deform modifier on a copy of it, applied it (collapse the modifier), and created a hair particle system (middle). You can see that the normals are way off, they point in a different angle than the normals of the faces. I then created a copy of it, created a cube, used the same particle system on the new cube, and removed it from the problem mesh. Then joined them together (3), this seems to repair it after the fact.
I already have a workaround, which is create another object, in my case a cube, add the particle system there, and then join it with the faulty object.
But what am I doing wrong to get this problem in the first place?
A link to the testcase can be found here: http://s000.tinyupload.com/index.php?file_id=91560319569059047793
I am using Blender version 2.76b.