That was due to a current limitation on dag system.. that leads to cyclic dependencies.
So now you can attach the origin of a simpledeform to an empty and mark whether its
affected by the relative position of empty or the global one.
brecht found a workarround to solve the cyclic dependency by
using a parent of both the mesh and the control empty:
empty_parent
|
|-> empty controlling simpledeform
|-> mesh with simpledeform modifier
* Added "Lock axis" options on taper and strech/squash (suggested by ZanQdo)
* Better control of deform factor (suggested by ZanQdo)
* Added eModifierTypeFlag_AcceptsCVs (so it now accepts both curves and meshes)
*Fixed a few UI things
*Make SimpleDeform and Shrinkwrap to use vertexgroup_get_vertex_weight, a similar function
"static float vert_weight(MDeformVert *dvert, int group)" existed on modifier.c, changed
it a bit and moved into BKE_deform.h
