pranav_jog 0 Light Poster

I have a form in my page and I have used the following code:

Page.RegisterStartupScript("SetInitialFocus", _
"<script>document.getElementById('" & TextBox21.ClientID & _
"').focus();</script>")


        TextBox21.Attributes.Add("onkeydown", _
"if(event.which || event.keyCode)" & _
"{if ((event.which == 9) || (event.keyCode == 9)) " & _
"{document.getElementById('" & txtpass.ClientID & _
"').focus();return false;}} else {return true}; ")

where textbox21 is my 1st textbox & then txtpass is next one.after that button is present, after tabbing from button i moved to the textbox21 but in this case i want to move towards address bar, how to solve this??????????????
i.e
when it gets to the last input field, instead of tabbing to the address bar, it tabs to the 1st field, so how to switch to address bar

thanks