Hello,
A little difficult to explain, but here is my example:
<script runat="server">
protected void btnTest_Click(object sender, EventArgs e)
{
lblTest.Text = "Clicked!";
}
</script>
<ExtJS:ViewPort runat="server" AutoHeight="True" AutoWidth="True" MonitorResize="True" Stateful="True">
<Content>
<ExtJS:BorderLayout runat="server" RenderHidden="True">
<Center Collapsible="False" CollapseMode="Mini" Split="True" MinWidth="825">
<ExtJS:Panel runat="server" AutoScroll="True" AutoWidth="True" Border="True">
<Content>
<asp:UpdatePanel runat="server">
<ContentTemplate>
<ExtJS:TabPanel ID="tabsCustomer" runat="server" ActiveTab="0" AutoHeight="True" AutoWidth="True">
<Tabs>
<ExtJS:Tab ID="tabCustomerSearch" runat="server" Title="Customer Search" AutoHeight="True" AutoWidth="True">
<Content>
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
Word<br />
<asp:UpdatePanel runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Label ID="lblTest" runat="server" Text="Nothing" />
<asp:Button ID="btnTest" runat="server" Text="Test" onclick="btnTest_Click" />
</ContentTemplate>
</asp:UpdatePanel>
</Content>
</ExtJS:Tab>
</Tabs>
</ExtJS:TabPanel>
</ContentTemplate>
</asp:UpdatePanel>
</Content>
</ExtJS:Panel>
</Center>
</ExtJS:BorderLayout>
</Content>
</ExtJS:ViewPort>
When the button is clicked, it scrolls to the top of the TabPanel again.
However, remove the UpdatePanel surrounding the TabPanel and it works.
Any ideas? Very annoying in my solution 
Cheers,
Timothy
----
Timothy Grant Vogelsang
tvogelsang [at] gmail [dot] com
Coolite Toolkit 0.7 SVN (Professional Edition)
Microsoft .NET Framework 2.0
Microsoft ASP.NET Ajax 1.0