ajax control toolkit balloon popup extender onHover

Question

I have a couple of asp:Labels on my page and what I would like to do is, when a user hovers over a label, the balloon pop up is displayed which has additional information.

Here is the code:

<asp:Label runat="server" ID="lbl1_2" Text="I am a label"></asp:Label>
                                <asp:Panel runat="server" ID="pnl1_2" Enabled="false">
                                    This is some random text for display purpose.
                                </asp:Panel>
                                <ajaxToolkit:BalloonPopupExtender ID="BalloonPopupExtender1" runat="server"
                                TargetControlID="lbl1_2"
                                BalloonPopupControlID="pnl1_2"
                                Position="BottomRight" 
                                BalloonStyle="Rectangle"
                                BalloonSize="Medium"
                                UseShadow="true" 
                                ScrollBars="Auto"
                                DisplayOnMouseOver="true"
                                DisplayOnFocus="false"
                                DisplayOnClick="false" />

That works fine but one caveat, when I hover over the label the balloon popup is displayed but when I hover off it doesn't go away. I must hover over another label to make it go away and display the balloon or click somewhere on the page.

How can I make it autohide when you hover off a label? Is it even possible?