SEC. 1141. DIMETHOXY BUTANONE (DMB). Subchapter II of chapter 99 is amended by inserting in the numerical sequence the following new heading: “ 9902.29.16 4,4-Dimethoxy-2-butanone (CAS No. 5436–21–5) (provided for in subheading 2914.50.50) Free No change No change On or before 12/31/2003 ”.