We are having concurrency issues with a third party application. Seems the application developers knew about concurent updates and locking issues, but some of their code doesn't use locking hints to limit to single rows. Especially when they inserting a new object level record (inserts single row in all tables). Needless to say they were asking for this kind of trouble when developing such a highly non-normalized data structure, that is another blog entry or two.

Sequential convoy pattern is actually simple to impliment if you are familiar with how subscriptions work, and can decide on what uniquely identifies the group of messages you wish to correlate. I used this pattern and am correlating to the receive location, almost seems like cheating doesn't it?

Sequential Convoy Aggregator Pattern in BizTalk Server 2004