Link/Refer Javascript file in aspx page

Atlast i got the solution........, i am suppose to include the file in script tag inside form. This
is pretty interesting. Same wont work if its inside header tag.
This can also be added b4 html tag, the problem is, addin it there shall change the whole formatting of the page.

<_form id="form1" runat="server">
<_script src="JavaScript/CommonValidation.js" type="text/javascript">

References
http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=418083&SiteID=1
http://forums.asp.net/t/908248.aspx