Autodock_segmentation_fault



hi all,
 could anybody tell me, how large a ligand can autodock handle? Even after
 setting the stacksize to unlimited, the autotors is giving segmentation
 fault, when I am running it on a molecule like CoA. Is this problem
 because of the big size of ligand (bigger than normal small organic
 molecules). Is there any subroutine in autodock which can automatically
 define the torsions in a ligand. I have using Autodock on my PC
 running on Linux Red-hat 7.3 OS.
 Thanks in advance,
 Gyan.