I think you have to apply a Css style for that. Unfortunately, I don't remember the name of the style to apply. However, I did see something like this within the past week. Someone asked in this form how to make a div tag have scrollbars. This is the same thing you need, as a panel renders as a div tag. Hope this helps somewhat
Is there a scrollbar feature for Panel Web Objects in ASP.NET and, if so, how do you turn it on?
TIA...