Coda Popup Bubbles problem on parent div overflow is scroll?

I have a list of online users containing only names. I am using Coda Popup Bubbles to show more details on mouse over of an online user's name. It shows a popup containing the user's details.

I have added overflow:auto and a fixed height to the list div, so that it will开发者_如何学JAVA scroll in the case of a large number of online users. This user list is loaded dynamically using an ajax request.

Now the problem is, for first 2-3 users (or for users at top of list) the popup is not displaying correctly. It only displays partially - the list's top border is like a boundary for the popup and the popup above the border is not displaying. I noticed that if I remove overflow:auto then it works perfectly.

No issue regarding z-index.

I didn't get any good solution on this, so finally I changed popup plugin.

I used this.