Akhtar v. Gonzales, 450 F.3d 587 (5th Cir. May 23, 2006) (regulation precluding applications for adjustment of status from "paroled" "arriving aliens" in removal proceedings, 8 C.F.R. 245.1(c)(8) (1997), is not ultra vires to statute).
http://caselaw.lp.findlaw.com/data2/circs/5th/0460497cv0p.pdf