Under what conditions may the assets of qualified plans under § 401(a),
individual retirement accounts (IRAs) under § 408 (including Roth IRAs under §408A), and eligible governmental plans under § 457(b) be pooled in a group trust described in Rev. Rul. 81-100 with the assets of custodial accounts under § 403(b)(7), retirement income accounts under § 403(b)(9), and governmental plans under § 401(a)(24) without affecting the tax status of these entities or the group trust?
