change content page to another master page.

Hi,
I am using ASP.NET 2.0 and C#.
I have a master page and 5 content pages. I created another master page and want 2 of the content pages,which were under master1.master to master2.master.
For example, if the content page is called myhome.aspx, previously i had:
<%@ Page Language="C#" MasterPageFile="~/Master1.master" Title="MyHome Page"%>
I tried to change it to point it to another master page as:
<%@ Page Language="C#" MasterPageFile="~/Master2.master" Title="MyHome Page"%>
But the content page is still refering the Master1.master only..
How to change the content page to another master page.
Thank you.
 
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