I described the scenerio that we are discussing in this fragment poorly... > Also note that the 'lost 204' scenerio is only one case where > the EbXML Send - HTTP Send - HTTP 204 - EbXML Receive sequence breaks > down. Even plain process multitasking could result in that > sequence being violated. This scenerio (event sequence) would be better written as: 1. EbXML Send From A 2. HTTP POST A -> B 3. EbXML Receive at B 4. HTTP 204 B -> A 5. EbXML Ack Send From B 6. HTTP POST B -> A 7. EbXML Ack Receive at A 8. HTTP 204 A -> B