what does FMail use for its duplicate detection, please?

on this system, i see numerous false positive duplicates that have passed
through the fastecho system of my uplink... i'm trying to track down why
FMail would think they are duplicates when FE has not... the FE system is
using its largest dupe database option...

)\/(ark

One of the great tragedies of life is the murder of a beautiful theory by a
gang of brutal facts. --Benjamin Franklin

--- FMail/Win32 1.60