function initSearchBox(){
	var inputs = document.getElementById('search').getElementsByTagName('input');
	for (i = 0 ; i < inputs.length; i++){
		if (inputs[i].type == 'submit') inputs[i].className += ' btn';
	}
}

if (window.attachEvent){
	window.attachEvent('onload', initSearchBox);
} else if (window.addEventListener){
	window.addEventListener('load', initSearchBox, false);
}