Question with UpdatePanel Partial Page postback

[Scooby Dog]

Could Some help:

I have a page with a (gridview nested within a gridview) in an
UpdatePanel (UpdateMode="Conditional"). The nested gridview drops down when
you click on an arrow and then you can click on each subgrid rows command
field. The gridviews are loaded from the Page_Load event. When I click on
the commandfield in the subgrid the Page_Load fires during the partial page
postback. From what I have read this is normal with UpdatePanels. But What
I don't understand is why both Page.IsPostBack and
ScriptManager.GetCurrent(Page).IsInAsyncPostBack test false after I click on
the command field in my grid. I need to stop the rebinding of the gridviews
( which causes the subgrid to collapse ) when the command field is clicked.
Also: I am using MasterPages and the <asp:ScriptManager ID="ScriptManager1"
runat="server"> </asp:ScriptManager> is located in my mater page form
section.


Would anyone have any suggestions how to test if a partial page postback is
occuring


Here is a link to the page source: http://pastebin.org/153774

here is a link to the code behind: http://pastebin.org/153781



Thanks


Dave.