Here is the latest mortgagee letter, I believe. I'm sure my friends here will be sure to correct me if it's not.
http://www.HUD.gov/offices/adm/hudclips/letters/mortgagee/files/05-48ml.doc
Here is HUD's page for lead base paint
http://www.HUD.gov/offices/hsg/sfh/ref/sfh1-18d.cfm
1. General Requirements - For all properties built before January 1, 1978, the appraiser must inspect ALL interior and exterior surfaces, such as walls, stairs, deck, porch, railing, eaves, windows, doors, fences, detached garages and other outbuildings and appurtenant structures for defective paint surfaces (i.e. chipping, peeling or flaking paint) and report defective conditions in the appraisal report.
note: FHA approved encapsulating paint (that conforms to ASTM Standard E-1795) should be used on lead based paint issues. (which most appraisers do not mention)