Non-blocking J2EE calls

We wish to connect fat clients (in our case Powerbuilder) to a J2EE environment (Weblogic). We also need to make some of the calls from the fat client non-blocking (asynchronous). With many clients, JMS was rejected as a mechanism.
Our first solution, which works as a prototype, was to package a Java bean as an OLE object and deploy it to the client. This bean could make the calls non-blocking. However there are registry issues (the packaging implies a pre-defined directory structure), we need a JRE on every client and 15Mb of weblogic jars (aaargh), so it only really works as a prototype.
The next (current) solution is a C dll that can be called from Powerbuilder and uses a socket to talk to a Java J2EE Gateway on the server. This Gateway makes the system non-blocking and calls the EJBs. This is clearly easier in terms of configuring the client.
Ideally we would like to drop the Gateway by finding a non-blocking way to get into J2EE from the C dll but the only methods we have thought of:
- simulating an HTTP servlet call
- SOAP
are synchronous (or appear to be, my knowledge of SOAP is limited).
Has anyone come across other ways of getting non-blocking communications with J2EE?

CORBA, this is what it was designed to do, but it is not not a light weight solution.

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check this thread...
[Error : DBIF_RSQL_SQL_ERROR;
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Henrik
LV since v3.1
“ground” is a convenient fantasy
'˙˙˙˙uıɐƃɐ lɐıp puɐ °06 ǝuoɥd ɹnoʎ uɹnʇ ǝsɐǝld 'ʎɹɐuıƃɐɯı sı pǝlɐıp ǝʌɐɥ noʎ ɹǝqɯnu ǝɥʇ'

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Non-blocking J2EE calls

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