13.5.4.4 To Cause Messages to Be Reprocessed

When a converter script encounters a temporary resource problem (for example, the system can't connect to an external server, a needed file is locked, and so on), you can use PMDF_AGN to tell the conversion channel to consider processing messages that have encountered a temporary error. The MTA will record a "Q" status message in the mail.log_current, retain the message in the conversion channel, and retry the processing later.

Add the following line to your conversion script:

echo "STATUS=178028698" >> $OUTPUT_OPTIONS