AS4oo AKA iSeries and webMethods performance

Does anybody have suggestions how to architect AS/400 to Integration Server bidirectional communications? If straight JDBC from IS is used, there are performance problems related to the overhead of opening / closing db connection every time you do something (and if you try to do connection pooling, then there are problems with connection persistency – or rather lack thereof – and connectivity in general). For initiating flows on Integration Server from AS/400 so far we’ve used client.jar, but having trigger that has to in-process start jvm and launch a flow is performance nightmare. 98% of processing is overhead!
Right now we’re thinking of using data queues… but I don’t want to suggest solutions before I hear from somebody.
Thanks in advance - Tomek

we at Abbott Labs are also facing the performance problem on AS/400 with IS . Major problem is overhead on CPU. IT consume all the resources and through out of memory error.
Can you suggest us some tips with your experience on AS/400.