HibernateEntityManager hem = (HibernateEntityManager) em.getDelegate();
try {
YFTheme theme = hem.find(YFTheme.class, themeId);
if (theme.getActive()) {
theme.setActive(false);
hem.merge(theme);
} else {
YFTheme currentTheme = this.getCurrentTheme();
if (currentTheme != null) {
currentTheme.setActive(false);
hem.merge(currentTheme);