Try this:

<asp:ImageButton
id="ImageButton1"
ImageUrl="button1.gif”

onmouseover="this.src='~/URL OF MOUSE OVER IMAGE'"
onmouseout="this.src='~/URL OF MOUSE OUT IMAGE'"

OTHER PROPERTIES HERE

runat="server">

</asp:ImageButton>

In VS2005 the code section: "onmouseover /onmouseout" may be highlighted as
wrong but it will work just fine in IE and Firefox.

The full MSDN article is here:
http://msdn2.microsoft.com/en-us/library/Aa479011.aspx#aspnet-usingjavascript_topic03

Hope this helps

James Page

dg to excel and field format
I'll buy you a latte....
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