Can somebody respond to the question???

I guess a naive workaround to this problem is to crete a service that reads 1 message(A). Then create another (B) one that consumes (A) 3 times storing the results in variables for future manipulation. The proccess wil consist in putting the 3 messages in a queue ((A) will get them), but B will be listening in a diferent one, so when you finish putting the 3 messages you will send a dummie one informing B to start his "orchestration". If more than 3 messages are put in A´s queue you ´ll probably have to manipulate the Back End URL during runtime or something to retrieve the messages by id (informated in the dummie perhaps). This is only one opinion but the bottom line is that you ´ll have to start playing with the different tools.

Hope it helps.

Actually it is very simple to do this in Datapower using a new feature called "event sync.
The pattern you are dealing with is called Basic callback pattern or in laymans workd "asynchronous request response" but in your case you are sending more than one response. Ideally, from design perspective, these responses should be aggregated before sent to datapower unlesss they are coming from 3 diferent sources.
In traditional MQ world, the correlation id on these responses can be used to correlate them with a request. But if you have more than 1 response, that creates complexity even if you use Message Broker since you have to customize your replay pattern.

Since your responses are asynchonous, you could setup a 2nd MultiProtocol Gateway on back of first MPG (that is bridging the protocol) to use more than one Front Side Protocol Handler polling a range of queues. Then in your policy, you can aggregate these messages using whatever mechanism (variables, stylesheet etc) and then drop the response message with appropriate Cororelation id on the reply queue of the first MPG.