public function checkAttribute($attribute, $ocls)
    {
        foreach ($ocls as $ocl) {
            $ocl_entry = $this->get('objectclass', $ocl);
            $ocl_may_attrs  = $this->may($ocl);
            $ocl_must_attrs = $this->must($ocl);
            if (is_array($ocl_may_attrs) && in_array($attribute, $ocl_may_attrs)) {
                return true;
            }
            if (is_array($ocl_must_attrs) && in_array($attribute, $ocl_must_attrs)) {
                return true;
            }
        }
        return false; // no ocl for the ocls found.
    }