Apparently you can hookup events by specifying the event and handler in the markup. (I say apparently as I do not actually have the control to play with at this moment.)
<cc1:Accordion
ID="AccordionResults"
runat="server"
DataSourceID="SqlDataSourceResults"
SelectedIndex="-1"
RequireOpenedPane="false"
FadeTransitions="true"
HeaderCssClass="accordionHeader"
HeaderSelectedCssClass="accordionHeaderSelected"
ContentCssClass="accordionContent"
Width="800px"
OnItemCreated="InitPanes" />
And
onItemCreated
calls:
Protected Sub InitPanes(ByVal sender As Object, ByVal e As AjaxControlToolkit.AccordionItemEventArgs)
Dim myAccordionPane As AjaxControlToolkit.AccordionContentPanel = CType(e.AccordionItem, AjaxControlToolkit.AccordionContentPanel)
Dim workAroundLabel As New Label
workAroundLabel.Visible = False
myAccordionPane.Controls.Add(workAroundLabel)
End Sub