A method and system are provided for transactional messaging support in connected messaging networks. A first messaging network is provided which does not support transactional processing and a second messaging network is provided which does support transactional processing. A proxy application is provided between the first and second messaging networks. The proxy application receives messages from a first application on the first messaging network, the messages including instructions regarding transactional processing of the messages, and forwards the messages to the second messaging network using a transactional processing supported by the second messaging network.