Role_delegation and role_limits

When I activate the module role_delegation, the module role_limits doesn't work.
It's because role_limits controls the number of users when "activate" is a parameter of the hook_user.
So, all is working if I replace the code :

/**
 * Implementation of hook_user().
 */
function role_delegation_user($op, &$edit, &$account, $category = NULL) {
  if ($op != 'insert' && $op != 'submit' ) {
    return;
  } 

with:

/**
 * Implementation of hook_user().
 */
function role_delegation_user($op, &$edit, &$account, $category = NULL) {
  if ($op != 'insert' && $op != 'submit' && $op != 'validate') {
    return;
  }