var defaultButton = null;

if(document.onkeypress){

	document.onkeypress() = function(){
		if (defaultButton == null || window.event.keyCode != 13) 
			return;
				
		defaultButton.click();
		window.event.returnValue = false;
				
		return false;
	}
}												

if(document.onkeydown){

	document.onkeydown() = function(){
		if (defaultButton == null || window.event.keyCode != 13) 
			return;
				
		defaultButton.click();
		window.event.returnValue = false;
				
		return false;
	}
}