<pre>
<SCRIPT language=javascript>
var base_foo;
function foo(yourname){
alert('Hello ' + yourname);
}
base_foo = foo;
foo = function(yourname){ alert(‘(overide) Hello ‘ + yourname); } </SCRIPT> </pre></code>From http://dataerror.blogspot.com/2005/08/javascript-function-overriding-part-2.html