so again we had trouble with Jitterbit since there is no Documentation like Salesforce has. If you are using Salesforce and you are trying to send Outbound messages be aware that they will be send in batch.
So in Jitterbit you have to create a Hosted Web Service, copy the URL to the Outbound Message, download the WSDL from the Outbound Message and upload it to the Hosted Web Service you created in Jitterbit. Bit confusing but when you do it you'll get it right.
After the Hosted Web Service you need to create a Transformation that uses a File Format to 'save' in global variables the record.
In our case we needed to call a Stored Procedure (using script in jitterbit) afterwards and this is where we had the problems. It only processed 1 record at a time even if the Outbound Message was sending more than once.
So the solution to this is the following:
1. Do no run the script with a 'on success' instruction of the first Operation (the Hosted Web Service).
2. Go back to the transformation where you are 'saving' in the global variables and go to the last one.
3. Run the next operation (the script that executes the SP) with this command: RunOperation("<TAG>Operations/Insert SP</TAG>", false);
And that one does the magic.
Have fun, Cheers.