Thanks HuiSheng, ya I'd seen that but it looked pretty complicated and heavyweight, particularly triggering DB write and transactions for each such asynch node. In the fully in-process web-request-processing application I'm looking at I want to avoid transactions altogether. Looks like either I couldcreate and use my own lighter-weight MessageService implementation instead, or else do it another way e.g. w/ custom Fork and Join node implementations.
Chris