Smarts Trap Processing Question

We are using one of the Notification user defined fields to show the ticket created from an associated escalation script. When an alert is sent to the Notification console the script runs it creates a ticket and populates the UserDefined 7 field. The problem I am having is if there is another trap matching the same event then the trap over-writes this UserDefined 7 field.

Is there a way to configure the SNMP trap adaptor to not update this UserDefined 7 field either in the trap_mgr.conf or using an ASL script?