How joint liabilities devolve on the death of any one of the joint promisor?

The Section 42 of ‘the Indian Contract Act’ deals with this situation. It does not make any distinction between joint promises and several promises. According to the said section in the absence of any contrary in the contract, all the persons who made promise during their joint lives; after the death of any of the promisor, legal heirs / representative of deceased promisor along with surviving promisors; after the death of the last surviving promisor, the legal heirs, representatives of all the promisors, are bound to fulfill the promise.
But if the contract provides for any contrary intension the liability devolves according to the contract.