error handling

Just run into this error:

Warning: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1 query: SELECT u.mail, u.name FROM users u LEFT JOIN users_roles ur on u.uid = ur.uid WHERE

Which is caused by an exception to the following code in the function lightcrm_comment(). The exception in my case was that I hadn't set any roles so $roles=array(), an empty array.

 $roles = variable_get('lightcrm_mailroles', array());
        foreach ($roles as $role_k => $role_v) {
          if ( $role_v > 0 ) {
            if ( $role_where ) {
              $role_where .= ' OR ';
            }
            if ( $role_v == DRUPAL_AUTHENTICATED_RID ) {
              $role_where = '1';
            } else {
              $role_where = 'ur.rid = '. $role_v;
            }
          }
        }

A possible fix:
1. check if $roles is empty. If not proceed, else
2. set a drupal error message that notifies the admin user that no roles have been setup to receive lightcrm emails but nonetheless accept the user's comment/support request.