hola, así lo puedes solucionar
Código HTML:
<script type="text/javascript" src="http://prototypejs.org/assets/2008/9/29/prototype-1.6.0.3.js"></script>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.2.6/jquery.min.js"></script>
<script type="text/javascript">
jQuery.noConflict();
(function($){
$(document).ready(function(){
$("#jQuery").html( "LOAD jQuery!" );
});
})(jQuery);
Event.observe(window, 'load', function() {
$("Prototype").innerHTML = "LOAD Prototype!";
});
</script>
<p id="jQuery">jQuery</p>
<p id="Prototype">Prototype</p>
saludos
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