Index: branches/5.1.x/core/admin_templates/js/ajax_dropdown.js
===================================================================
diff -u -N -r14241 -r14442
--- branches/5.1.x/core/admin_templates/js/ajax_dropdown.js	(.../ajax_dropdown.js)	(revision 14241)
+++ branches/5.1.x/core/admin_templates/js/ajax_dropdown.js	(.../ajax_dropdown.js)	(revision 14442)
@@ -70,13 +70,11 @@
 
 
 function AJAXDropDown(input_id, suggest_url_callback, get_value_callback, $custom_params) {
-	this.params = {
-		useTags: false,
-		maxWidth: false
-	};
+	this.useTags = false;
+	this.maxWidth = false;
 
 	if ($custom_params !== undefined) {
-		$.extend(this.params, $custom_params);
+		$.extend(this, $custom_params);
 	}
 
 	this.Input = document.getElementById(input_id);
@@ -390,15 +388,15 @@
 	var $input_width = $input.outerWidth();
 	var $input_height = $input.outerHeight();
 
-	if (this.params.maxWidth === false) {
+	if (this.maxWidth === false) {
 		$new_box_width = $input.width();
 
 		if (document.all) {
 			$new_box_width += ($input_width - $input.innerWidth()); // add borders for IE
 		}
 	}
 	else {
-		var $new_box_width = this.params.maxWidth;
+		var $new_box_width = this.maxWidth;
 	}
 
 	if ($box.width() < $new_box_width) {
@@ -415,6 +413,11 @@
 		$box_top -= ($input_height + $box_height);
 	}
 
+	var $scroll_container = $($input).parents('#scroll_container_container');
+	var $scroll_container_offset_top = $scroll_container.length > 0 ? $scroll_container.scrollTop() - $scroll_container.offset().top : 0;
+
+	$box_top += $scroll_container_offset_top;
+
 	$(this.Box)
 	.css(
 		{