function validateform()
{
	
    if ( document.searchform.searchterm.value == "" )
    {
        alert ( "Por favor, insira um termo de pesquisa." );
        return false;
    }
	else
    {
		var url = document.searchform.site.options[document.searchform.site.selectedIndex].value
		url = url + document.searchform.searchterm.value;
		window.location.href = url;
		return true;
    }
	
}