Hi Massimo, As far as I've tested, the following css must be applied after loading both css files (web2py's default + jqueryui's smoothness):
.ui-widget, .ui-widget-content, .ui-widget-header, .ui-widget input,
.ui-widget select, .ui-widget textarea, .ui-widget button { font:13px/1.231
sans-serif; font-size: 100%; color: #444; }
.ui-button-text-only .ui-button-text { padding: 0 1em; }
Take care,
Carlos

