After receiving a transaction my AS2 system sends the MDN and writes to the message log something like this:

Outbound MDN created for AS2 message "mendelson_opensource_AS2-1565824101531-12@Host2_Host1", state set to [mendelson_opensource_AS2-1565823918260-12@Host1_Host2]

So instead of the MDN state the initial transaction ID was logged.
(This happens no matter if the initial transaction was succesfully processed or not.)

From "ResourceBundleAS2MessagePacker.java":

{"mdn.created", "Outbound MDN created for AS2 message \"{0}\", state set to [{1}]." }

From "AS2MDNCreation.java":

if (dispositionState.indexOf("error") >= 0) {
if (this.logger != null) {
this.logger.log(Level.SEVERE, this.rb.getResourceString("mdn.created",
new Object[]{
mdnInfo.getMessageId(), mdnInfo.getRelatedMessageId(), dispositionState
}), mdnInfo);
}
} else {
if (this.logger != null) {
this.logger.log(Level.FINE, this.rb.getResourceString("mdn.created",
new Object[]{
mdnInfo.getMessageId(), mdnInfo.getRelatedMessageId(), dispositionState
}), mdnInfo);
}
}