Nice extra info...
<form id="form1" runat="server" defaultbutton="Button1" defaultfocus="Button2">



On the posting page...
...We have a textbox and a calendar control and a button to initiate the post...

Button Property "PostBackURL" set to page to post to





On the page to post to...

dim t as TextBox = CType(PreviousPage.FindControl("TextBox1"), TextBox)
dim c as Calendar = Ctype(PreviousPage.FindControl("Calendar1"),Calendar)
Label1.Text = String.Format("Hello {0}, you clicked on {1}",t.text,c.SelectedDate)