How to catch and log the exceptions or error messages displayed in the MWA screen

We have a requirement to catch the serial number exception like 'duplicate serial number' or 'this serial number already existys'  while entering the cycle count.These messages appear on the screen but not sure if they are logged anywhere.We actuially want to know which serial number were not valid and gave the error after completing the cycle count.So that we can have some kind of reporting and we can correct those serial number outside cycle count process.

We do not have the java source code so really have no idea how to catch these exceptiins and report it later.How to know which database function is being called to perform validation/transaction in MWA screen.