(a) In general. For purposes of section 4975(e)(8) and this section, the term “qualifying employer security” means an employer security which is:

(1) Stock or otherwise an equity security, or

(2) A bond, debenture, note, or certificate or other evidence of indebtedness which is described in paragraphs (1), (2), and (3) of section 503(e).

(b) Special rule. In determining whether a bond, debenture, note, or certificate or other evidence of indebtedness is described in paragraphs (1), (2), and (3) of section 503(e), any organization described in section 401(a) shall be treated as an organization subject to the provisions of section 503.