Tony,
I would be intersted to find out if these are TCP/IP connections AND if you are using application level acknowledgment.
If you are not using any acknowledgment protocol, then I find no surprise you might be missing messages. A resend could very well work.
If you are using an acknowledgment protocol, then check the SAMT for the acknowledgments and the foreign system to insure acks were properly processed.
Like Jim Cobane said if they are not in the inbound SMAT, then Cloverleaf did not get them.
Jim Kosloskey
email: jim.kosloskey@jim-kosloskey.com 29+ years Cloverleaf, 59 years IT - old fart.