diff -u -r1.2 jquery.ui.datepicker.js
--- jquery.ui.datepicker.js	28 Oct 2010 11:41:32 -0000	1.2
+++ jquery.ui.datepicker.js	4 Nov 2010 14:23:34 -0000
@@ -615,7 +615,7 @@
 			$.datepicker._pos[1] += input.offsetHeight; // add the height
 		}
 		var isFixed = false;
-		$(input).parents().each(function() {
+		$(input).parents(":not(body,html)").each(function() {
 			isFixed |= $(this).css('position') == 'fixed';
 			return !isFixed;
 		});