Display vertical scrollbars in a dynamic CheckBoxList with in IE?? (works fine in Chrome and FF)

Below is a dynamic CheckBoxList control that I've added to my webpage, in Chrome and Firefox this works just fine, displaying the vertical scrollbar correctly. However, IE does not display scrollbars, it just lists a large list without scrolls. What do i need to do to get IE to show this correctly as the other two browsers do?

var pMultiValueList = new CheckBoxList();
pMultiValueList.St开发者_StackOverflow中文版yle.Add("Position", "relative");
pMultiValueList.Style.Add("overflow", "auto");
pMultiValueList.Style.Add("display", "block");

Thanks!!

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Try giving it a fixed height or number of items to show.

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Created an ascx of a checkboxlist surrounded by div and used that. Works now.