Suvorov v. Gonzales, 441 F.3d 618 (8th Cir. Mar. 28, 2006) (courts lack jurisdiction to review questions of fact underlying discretionary decisions of the Attorney General involving waivers of inadmissibility or hardship waivers for purposes of relief from removal).
http://caselaw.lp.findlaw.com/data2/circs/8th/043911p.pdf