Smith v. Gonzales, ___ F.3d ___ (5th Cir. Oct. 24, 2006) (second state misdemeanor conviction for possession of marijuana did not qualify as an "aggravated felony" for immigration purposes because second possession only becomes a felony under federal law upon conviction of a second offense after conviction of a prior simple possession; in this case, there was no effective prior conviction under 21 U.S.C. 844(a) because the first conviction was not yet final).
http://caselaw.lp.findlaw.com/data2/circs/5th/0660020cv0p.pdf