I believe I had to use UDF's for one customer. A common problem for us was missing codes from Zip Code maintenance. EDI data is pushed into a UDF, and simple column post validate script copied from there to the Sage field... then we have an automated alert for when the UDF doesn't match the Sage field (i.e. a missing Zip code). If you're in a rush for a solution, I expect something similar would work for you (with a checkbox to silence the alert, once someone has manually fixed the address).
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Kevin Moyes
Technical Systems Analyst
Munjal White Consulting Co.
Toronto ON
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