§ 5-1109. Written irrevocable offer. Except as otherwise provided in
section 2-205 of the uniform commercial code with respect to an offer by
a merchant to buy or sell goods, when an offer to enter into a contract
is made in a writing signed by the offeror, or by his agent, which
states that the offer is irrevocable during a period set forth or until
a time fixed, the offer shall not be revocable during such period or
until such time because of the absence of consideration for the
assurance of irrevocability. When such a writing states that the offer
is irrevocable but does not state any period or time of irrevocability,
it shall be construed to state that the offer is irrevocable for a
reasonable time.