/**
  * @return boolean
  * @throws User_UserGroupNotFoundException
  * @throws User_UserGroupNameInvalidException
  */
 public function updateUserGroup(User_ForgeUgroup $user_group)
 {
     $row = $this->dao->getForgeUGroup($user_group->getId());
     if (!$row) {
         throw new User_UserGroupNotFoundException($user_group->getId());
     }
     if (!$this->userGroupHasModifications($user_group, $row)) {
         return true;
     }
     return $this->dao->updateForgeUGroup($user_group->getId(), $user_group->getName(), $user_group->getDescription());
 }