TabContainer/TabPanel FindControl

Would you mind posting the markup of the Tab?

Not sure what's going on, but it works today... no change in code. As you can see below, the TabContainer code is about as simple as it gets. Was testing it to see how it works.

Strangely enough, it also seems to work without declaring anything or running a FindControl: MyTextBox.Text ="Hello"

XML
<asp:ScriptManagerID="ScriptManager1"runat="server">
</asp:ScriptManager>
<cc1:TabContainerID="TabContainer1"runat="server"ActiveTabIndex="0">
<cc1:TabPanelID="TabPanel1"runat="server"HeaderText="TabPanel1">
<ContentTemplate>
<asp:TextBoxID="MyTextBox"runat="server"></asp:TextBox>
</ContentTemplate>
</cc1:TabPanel>
<cc1:TabPanelID="TabPanel2"runat="server"HeaderText="TabPanel2">
</cc1:TabPanel>
</cc1:TabContainer>

CODEBEHIND
Sub Page_Load(ByVal senderAsObject,ByVal eAs System.EventArgs)HandlesMe.Load
'Dim TabContainer1 As AjaxControlToolkit.TabContainer = Page.FindControl("TabContainer1")
'Dim MyTextBox As TextBox = TabPanel1.FindControl("MyTextBox")
MyTextBox.Text ="Hello"
EndSub