A federal judge has declined to throw out a lawsuit accusing a Minnesota man of defaming his ex-wife in e-mails he sent to her employer in Illinois.In a written opinion, U.S. District Judge Elaine Bucklo rejected the argument that the courts in Illinois lack personal jurisdiction over Kenneth R. Campbell.Campbell’s communications with Inland Real Estate Investment Corp. in Oak Brook — which alleged his ex-wife had defrauded investors while working for a former employer and also was guilty of other &ldquo …