addStyle on jqOverlay not working

Has anyone been able to get the addstyle to work for the jqoverlay control.

I have tried almost everything I can think of to get the style to apply and nothing seems to work.

   Dim ol As clsJQuery.jqOverlay = New clsJQuery.jqOverlay("popup_" & ID, Me.PageName, False, "")
        ol.toolTip = tooltip
        ol.label = Label
        ol.className = ""
        ol.AddStyle("font-size : 18pt;")
        ol.overlayHTML = content.ToString

Any help or suggestions any one can offer would be great!