From the Legal Malpractice Insurance blog:
"On Monday, February 20, 2006, the Illinois Supreme Court submitted an opinion in a legal malpractice case, which has now changed the way the doctrine of void ab initio will be used in Illinois. For 92 years the Illinois supreme court have used the U.S. Supreme Court case Norton v. Shelby County as an example to follow in ruling a void ab initio scenario" Check their site for the case.