Image button problem.

Question

I m using image button on my webpage

   <asp:ImageButton ID="ImageButton1" runat="server"
                                ImageUrl="~/Images/Button/Button-Home.gif" onclick="ImageButton1_Click"
                                OnMouseOver="this.src='Images/Button/Button-Home2.gif'"
    onmouseout="this.src='Images/Button/Button-Home.gif'"
                                 />

By the above code i can able to chage image (Button-Home.gif   to   Button-Home2.gif )

Now my problem is that i want to fix image (Button-Home2.gif) fix if i click on the image button.
How can i do this?