(1) Trusts or plans which are entitled to the exemption from limitation as to their duration provided for in section 48-2001 shall be:

(a) Created by an employer or employers primarily for the benefit of some or all of the employees of such employer or employers, or the families or appointees of such employees, under any pension, profit-sharing, stock bonus, retirement, disability, death benefit, or other similar type of employee benefit plan;

(b) Contributed to by the employer or employees or both; and

(c) Existing for the purpose of distributing the earnings or principal, or earnings and principal, of the trust to or for the benefit of some or all of such employees, either before or after their employment ceases, or their families or appointees.

(2) In addition, in the case of such trusts hereafter created by public corporations, municipal corporations, or political subdivisions of this state, the trustee shall be qualified to act as a trustee and licensed to do business in Nebraska, the management of the affairs of the trust shall be carried on in this state, and the trust agreement shall contain provisions for termination of the trust and for substitution of trustees, by unilateral action of the public corporation, municipal corporation, or political subdivision which created the trust. If a qualified trust corporation licensed to do business in Nebraska with capital of not less than five hundred thousand dollars applies to the employer for appointment as successor trustee on a basis of cost for administering the trust, not in excess of the basis of cost then existing, no public corporation, municipal corporation, or political subdivision of this state shall incur any additional obligation, under existing agreements as to such trusts, which does not comply with this subsection. Any trust created which violates this subsection shall be void.